»Curriculum Vitae
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Address:
Department of Mathematics  Phone : 2547103165 
Sid Richardson Building  317B 
Baylor University  Fax: 2547103569 
Waco, Texas  Email: Lance_Littlejohn@baylor.edu 
767987328 
Education:
Institution 
Dates Attended  Degree Date  Degree 
University of Western Ontario  19701975  1975  BSc. 
University of Western Ontario  19751976  1976  M.A. 
Pennsylvania State University  19761981  1981  Ph.D. 
Academic Experience:
University of Western Ontario, 19751976; Teaching Assistant 
Pennsylvania State University, 19761981; Graduate Assistant 
The University of Texas at San Antonio, 19811983; Assistant Professor 
Utah State University, 19831987; Assistant Professor 
Utah State University, 19871993; Associate Professor 
Utah State University, 19932006; Full Professor 
Baylor University, 2007present; Full Professor and Chair of Department 
Baylor University, 2012  ; Associate Dean for Research, Graduate School 
Visiting Postions:
University of Surrey (England), 1987; Visiting Associate Professor 
University of South Africa, 1990; Visiting Associate Professor 
University of Wales, Cardiff, 19901991; Visiting Associate Professor 
Carlos III University, Madrid, Spain, 19992000; Visiting Full Professor 
Carlos III University, Madrid, Spain, 2002; Visiting Full Professor 
University of Gabes, Tunisia, Visiting Full Professor 
KAIST, Taejon, South Korea, 20022004; Visiting Full Professor 
Publications:
 1982
 1). Nonclassical orthogonal polynomials as solutions to second order differential equations", (with S.D. Shore), Canad. Math. Bull., 25(3), 1982, 291295.
 2). The Krall polynomials: a new class of orthogonal polynomials", Quaestiones Math., 5(3), 1982, 255265.
 1983
 3). "A singular sixth order differential equation with orthogonal polynomial eigenfunctions", (with A.M. Krall), in Lecture Notes in Mathematics, No. 964, 1983, Proceedings of Conference on Ordinary and Partial Differential Equations, Dundee, Scotland, 1982, SpringerVerlag, New York, 435444.
 4). "The Krall polynomials as solutions to a second order differential equation", Canad. Math. Bull., 26(4), 1983, 410417.
 5). "Symmetry factors for differential equations", Amer. Math. Monthly, 90(7), 1983, 462464.
 1984
 6). "On the classification of differential equations having orthogonal polynomial solutions", Ann. Mat. Pura Appl., 4, 1984, 3553.
 7). Weight distributions and moments for a certain class of orthogonal polynomial eigenfunctions", Proceedings of the Conference on Differential Equations, Birmingham, Alabama, NorthHolland Math. Studies, 92, 1984, 413419.
 1986
 8). Orthogonal polynomials and singular SturmLiouville systems I", (with A.M. Krall), Rocky Mountain J. Math., 16(3), 1986, 435479.
 9).An application of a new theorem on orthogonal polynomials and differential equations", Quaestiones Math., 10(1), 1986, 4961.
 1987
 10). "Distributional solutions of the hypergeometric differential equation", (with R.P. Kanwal), J. Math. Anal. Appl., 122(3), 1987, 325345.
 11). "On the classification of differential equations having orthogonal polynomial solutions II", (with A.M. Krall), Ann. Mat. Pura Appl., 4, 1987, 77102.
 12). "A curious set of numbers", (with A.M. Krall), Fibonacci Quarterly, 25(4), 1987, 352355.
 13). "SturmLiouville operators and orthogonal polynomials", (with A.M. Krall), Proceedings of Conference on Differential Equations, Bifurcation and Chaos, University of Toronto, 1986, in Oscillation, Bifurcation and Chaos, CMSAMS Colloquium Series, Volume 8, 1987, 247259.
 14). "Distributional solutions of ordinary differential equations", (with R.P. Kanwal and A.M. Krall), Proceedings of Conference on Differential Equations, Oscillation, Bifurcation and Chaos, University of Toronto, 1986, in Oscillation, Bifurcation and Chaos, CMSAMS Colloquium Series, Volume 8, 1987, 227246.
 1988
 15). "Differential operators and the Legendre type polynomials", (with W.N. Everitt), Differential and Integral Equations, 1(1), 1988, 97116.
 16). "A characterization of formally symmetric ordinary differential expressions", (with D. Race), in Differential Equations and Applications, Proceedings of International Conference on Theory and Applications of Differential Equations, Columbus, Ohio, March 1988, Ohio University Press, 164169.
 17). "Orthogonal polynomial solutions to ordinary and partial differential equations", Proceedings of International Conference on Orthogonal Polynomials and their Applications, Segovia, Spain, 1986, in Orthogonal Polynomials and their Applications, Lecture Notes in Mathematics, No. 1329, 1988, 98124.
 1989
 18). "Orthogonal polynomials in weighted Sobolev spaces", (with W.N. Everitt and S.C. Williams), Proceedings of International Conference on Orthogonal Polynomials and their Applications, Laredo, Spain, 1987, in Orthogonal polynomials and their Applications (editor: J. Vinuesa), Lecture Notes in Pure and Applied Mathematics, No. 117, Marcel Dekker, New York, 1989, 5373.
 1990
 19). "Orthogonal polynomials and higher order singular SturmLiouville systems", (with A.M. Krall), Acta Applicandae Mathematicae, 17, 1990, 99170.
 20). "Symmetry factors for differential equations with applications to orthogonal polynomials", Acta Mathematica Hungarica, 56(12), 1990, 5763.
 21). "Symmetric and symmetrisable ordinary differential expressions", (with D. Race), Proc. London Math. Soc., 1, 1990, 334356.
 22). "On some properties of the Legendre type linear differential expression", (with W.N. Everitt and A.M. Krall), Quaestiones Math., 13(1), 1990, 83106.
 23). "Rightdefinite spectral theory of selfadjoint differential operators with applications to orthogonal polynomials", (with W.N. Everitt and S.M. Loveland), in Polinomios Ortogonales Y Aplicaciones (editor: Luis Arias), Acta del VI Simposium, Proceedings of Conference on Orthogonal Polynomials and their Applications, Gijon, Spain, 1989, University of Oviedo, 1990, 132.
 24). "The density of polynomials in a weighted Sobolev space", (with W.N. Everitt), Rendiconti di Matematica, Roma, Series VII (10), 1990, 835852.
 1991
 25). "The leftdefinite Legendre type problem", (with W.N. Everitt and S.C. Williams), Journal of Constructive Approximation, 7, 1991, 485500.
 26). "Orthogonal polynomials and spectral theory: a survey", (with W.N. Everitt), Proceedings of Erice Conference on Orthogonal Polynomials and their Applications, in Orthogonal polynomials and their applications (editors: L. Gori, C. Brezinski, A. Ronveaux), IMACS Annals on Computing and Applied Mathematics, Volume 9, J.C. Baltzer AG, Basel, Switzerland, 1991, 2155.
 1992
 27). "Differential operators and the Laguerre type polynomials", (with W.N. Everitt, A.M. Krall and V.P. OnyangoOtieno), SIAM J. Math. Anal., 23(3), 1992, 722736.
 28). "The Legendre type operator in a leftdefinite Hilbert space", (with A.M. Krall and W.N. Everitt), Quaestiones Math., 15(4), 1992, 467475.
 29). "Discrete inequalities, orthogonal polynomials and the spectral theory of difference operators", (with W.D. Evans and B.M. Brown), Proc. Royal. Soc. London, Series A, (437), 1992, 355373.
 30). "A solution to the general Bessel moment problem",
(with K.H. Kwon, W.D. Evans, W.N. Everitt and A.M. Krall), in World
Scientific Series in Applied Analysis I, 1992, 205220.
 1993
 31). "Orthogonal polynomials and approximation in Sobolev spaces", (with W.N. Everitt and S.C. Williams), J. Comput. Appl. Math., 48, 1993, 6990.
 32). "Real orthogonalizing weights for Bessel polynomials", (with W.D. Evans, W.N. Everitt and K.H. Kwon), J. Comput. Appl. Math., 49, 1993, 5157.
 33). "Orthogonal polynomials and extensions of Copson's inequality", (with W.D. Evans and B.M. Brown), J. Comput. Appl. Math., 48, 1993, 3348.
 34). "Some properties of the sixthorder Legendretype
differential expression", (with W.N. Everitt and S.M. Loveland), Rendiconti di Matematica, 13, 1993, 773799.
 35). "The Legendre polynomials under a leftdefinite energy norm", (with A.M. Krall), Quaestiones Math., 16(4), 1993, 393403.
 36). "On the completeness of orthogonal polynomials in
leftdefinite Sobolev spaces", (with W.N. Everitt and R. Wellman), in Topics in Polynomials of One and Several Variables and their
Applications (editors: Th. M. Rassias, H.M. Srivastava, A.
Yanushauskas), World Scientific, Singapore, 1993, 173197.
 1994
 37). "Characterizations of classical type orthogonal polynomials", (with K.H. Kwon, J.K. Lee and B.H. Yoo), Proc. Amer. Math. Soc., 120(2), 1994, 485493.
 38). "Characterizations of orthogonal polynomials satisfying differential equations", (with K.H. Kwon and B.H. Yoo), SIAM J. Math. Anal., 25(3), 1994, 976990.
 39). "Properties of the operator domains of the fourthorder Legendretype differential expressions", (with W.N. Everitt and S.M. Loveland), Differential and Integral Equations, 7, 1994, 795810.
 40). "Polynomials orthogonal in a Sobolev space", (with A. Iserles), in Linear and complex analysis problem book II (editors: V.P. Havin and N.K. Nikolski), Lecture Notes in Mathematics, No. 1574, SpringerVerlag, New York, 1994, 190193.
 1995
 41). "On recurrence relations for Sobolev orthogonal polynomials", (with W.D. Evans, F. Marcellán, C. Markett, and A. Ronveaux), SIAM J. Math. Anal., 26(2), 1995, 446467.
 42). "The symmetric form of the Koekoek's Laguerre type differential equation", (with W.N. Everitt and R. Wellman), J. Comput. Appl. Math., 57, 1995, 115121.
 43). "The Laguerre type operator in a leftdefinite Hilbert space", (with W.N. Everitt, A.M. Krall and V.P. OnyangoOtieno), J. Math. Anal. Appl., 192, 1995, 460468.
 44). "The orthogonality of the Laguerre polynomials for positive integers ", (with K.H. Kwon), Annals of Numerical Mathematics, 2(14), 1995, 289303.
 45). "Sobolev orthogonal polynomials and spectral differential equations", (with K.H. Kwon, I.H. Jung and D.W. Lee), Trans. Amer. Math. Soc., 347(9), 1995, 36293643.
 46). "Differential equations and Sobolev orthogonality", (with K.H. Kwon, I.H. Jung and D.W. Lee), J. Comput. Appl. Math., 65, 1995, 173180.
 47). "Hermitian differential operators, distributions and bilinear forms", (with W.N. Everitt and K.H. Kwon), in Selecta Analytica, Virian Press, U.K., 1995, 7181.
 1996
 48). "Zeros of orthogonal polynomials in certain discrete Sobolev spaces", (with S.S. Han and K.H. Kwon), J. Comput. Appl. Math., 67, 1996, 309325.
 49). "New characterizations of classical orthogonal polynomials", (with K.H. Kwon and B.H. Yoo), Indag. Math. N.S., 7(2), 1996, 199213.
 50). "Sobolev orthogonal polynomials and second order differential equations II", (with K.H. Kwon and D.W. Lee), Bull. Korean Math. Soc., 33(1), 1996, 135170.
 1997
 51). "On the spectral analysis of the Laguerre polynomials for positive integers ", (with W.N. Everitt, K.H. Kwon and R. Wellman), in Spectral Theory and Computational Methods of SturmLiouville Problems, Lecture Notes in Pure and Applied Mathematics (editors: Don Hinton and Philip W. Schaefer), Volume 191, Marcel Dekker, New York, 1997, 251283.
 52). "Differential equations having orthogonal polynomial solutions", (with K.H. Kwon and D.W. Lee), J. Comput. Appl. Math., 80, 1997, 116.
 53). "Classification of classical orthogonal polynomials", (with K.H. Kwon), J. Korean Math. Soc., 34(4), 1997, 9731008.
 1998
 54). "A catalogue of HELP and HELPtype integral and series inequalities", (with M. Benammar, C. Bennewitz, M.J. Beynon, B.M. Brown, N.G.J. Dias, W.D. Evans, W.N. Everitt and V.G. Kirby), Recent Progress in Inequalities, Math. Appl., 430, 1998, 127160.
 55). "Sobolev orthogonal polynomials and secondorder differential equations", (with K.H. Kwon), Rocky Mountain J. Math., 28(2), 1998, 547594.
 1999
 56). "An Integral Operator with Applications", (with R S. Chisholm and W.N. Everitt), J. of Inequal. & Applications, 3(1999), 245266.
 57). "BochnerKrall orthogonal polynomials", (with K. H. Kwon and G. J. Yoon), Proceedings of International Workshop on Special Functions, Asymptotics, Harmonic Analysis and Mathematical Physics, Hong Kong, June 1999, World Scientific Publishers, 181193.
 58). "H.J.S. Smith and the Fermat two squares theorem", (with W.N. Everitt, S.J.R. Vorster, and F.W. Clarke), The American Mathematical Monthly, 106(7), 1999, 652665.
 2000
 59). "The leftdefinite spectral theory for the classical Hermite differential equation", (with W. N. Everitt and R. Wellman), J. Comput. Appl. Math. 121, 2000, 313330.
 2001
 60). "Orthogonal polynomial eigenfunctions of second order partial differential equations", (with K.H. Kwon and J.K. Lee), Trans. Amer. Math. Soc., 353(9), 36293647, 2001.
 61). "Orthogonal polynomial solutions to spectral type differential equations: Magnus' conjecture", (with K. H. Kwon, and G. J. Yoon), J. Approximation Theory 112, 189215, 2001.
 62). "Orthogonal polynomial solutions of linear ordinary differential equations", (with W. N. Everitt, K. H. Kwon, and R. Wellman), J. Comput. Appl. Math. 133 (2001), 85109.
 63). "Selfadjoint operators generated from nonLagrangian symmetric differential equations having orthogonal polynomial eigenfunctions", (with W.N. Everitt, K.H. Kwon, J.K. Lee, and S.C. Williams), Rocky Mountain J. Math., 31(3), 899937, 2001.
 2002
 64). "A general leftdefinite theory for certain selfadjoint operators with applications to differential equations", (with R. Wellman), J. Differential Equations, 181(2), 2002, 280339.
 65). "On generalized Riesz points", (with W.Y. Lee and R. Harte), J. Operator Theory, 47(2002), 187196.
 66). "On the rightdefinite and leftdefinite spectral theory of the Legendre polynomials", (with J. Arvesú and F. Marcellán), J. Comput. Anal. and Appl., 4(4)(2002), 363387.
 67). "On properties of the Legendre differential expression", (with W. N. Everitt and V. Marić), Result. Math. 42(2002), 4268.
 68). "Legendre polynomials, LegendreStirling numbers, and the leftdefinite spectral analysis of the Legendre differential expression", (with W. N. Everitt and R. Wellman), J. Comput. Appl. Math., 148(2002), 213238.
 2004
 69). "Orthogonal polynomials satisfying partial differential equations belonging to the basic class", (with J. K. Lee and B. H. Yoo), J. Korean Math. Soc. 41(2004), 10491070.
 70). "The fourthorder Besseltype differential equation", (with J. Das, W. N. Everitt, D. B. Hinton, and C. Markett), Applicable Analysis, 83(4) (2004), 325362.
 71). "On analytic sampling theory", (with A. García), J. Comput. Appl. Math., 171 (2004), 235246.
 72). "The Sobolev orthogonality and spectral analysis of the
Laguerre polynomials
for positive integers k", (with W. N. Everitt and R.
Wellman), J. Comput. Appl. Math., 171 (2004), 199234.
 2005
 73). "Additional properties of the fourthorder Besseltype differential equation", (with W. N. Everitt, H. Kalf, and C. Markett), Math. Nachr., 278(1213) (2005), 15381549.
 2006
 74). "A construction of real weight functions for certain orthogonal polynomials in two variables, (with J. K. Lee), J. Math. Anal. Appl. 319(2006), no. 2, 475493.
 75). "Sobolev orthogonal polynomials in two variables and secondorder partial differential equations", (with J. K. Lee), J. Math. Anal. Appl., 322(2006), no. 2, 10011017.
 76). "Construction of differential operators having BochnerKrall orthogonal polynomials as eigenfunctions", (with K. H. Kwon and G. J. Yoon), J. Math. Anal. Appl., 324(2006), 285303.
 77). "The fourthorder Bessel equation: eigenpackets and a generalized Hankel transform", (with W. N. Everitt, H. Kalf, and C. Markett), Integral Transforms Spec. Funct., 17(2006), no. 12, 845862.
 2007
 78). "Leftdefinite variations of the classical Fourier expansion theorem", (with A. Zettl), Electron. Trans. Numer. Anal., 27 (2007) 124139.
 79). "JacobiStirling numbers, Jacobi polynomials, and the leftdefinite analysis of the classical Jacobi differential expression", (with W. N. Everitt, K. H. Kwon, R. Wellman, and G. J. Yoon), J. Comput. Appl. Math., 208(2007) 2956.
 80). "Some remarks on classical Lagrangian symmetric differential expressions and their composite powers", (with W. N. Everitt and D. Tuncer), Adv. Dyn. Syst. Appl. 2(2), 2007, 187206.
 2008
 81). "Leftdefinite theory with applications to orthogonal polynomials ", (with A. Bruder, D. Tuncer, and R. Wellman), J. Comput. Appl. Math.,, 233(2010), 13801398.
 82). "A combinatorial interpretation of the LegendreStirling numbers", (with G. E. Andrews), Proc. Amer. Math. Soc., 137(8), 2009, 25812590.
 83). "Quasiseparation of the biharmonic partial differential equation", (with W. N. Everitt, B. T. Johannson, and C. Markett), IMA (Oxford) J. Appl. Math., 2009 74(5), 685709. .
 84). "Ghost matrices and a characterization of symmetric Sobolev bilinear forms", (with K. H. Kwon and G. J. Yoon), Linear Algebra Appl., 431 (2009), 104119.
 85). "Properties of the solutions of the fourthorder Besseltype differential equation", (with W. N. Everitt and C. Markett), J. Math. Anal. Appl., 359 (2009), 252264.
 2009
 86). "Variation of parameters and solutions of composite products of linear differential equations", (with J. L. López), J. Math. Anal. Appl., 369 (2010), 658670.
 87)."The LegendreStirling Numbers", (with G. E. Andrews and W. Gawronski), Discrete Math., 311 (2011), 12551272.
 2010
 88) ."Factorization of secondorder linear differential equations and LiouvilleNeumann expansions", (with E. García, J. L. López, and E. Pérez Sinusía), Mathematical and Computer Modelling, 57 (2013), 15141530.
 89) ."Nonclassical Jacobi polynomials and Sobolev orthogonality", (with A. Bruder), Results Math., 61(2012), no. 34, 283313.
 2011
 90) ."On the spectra of leftdefinite operators", (with R. Wellman), Complex Anal. Oper. Theory, Online: DOI 10.1007/s1178501101786, August 2011, 19 pages.
 91) ." The Legendre equation and its selfadjoint operators", (with A. Zettl), Electron. J. Diff. Equ., Vol. 2011 (2011), No. 69, pp. 133.
 92) ." The JacobiStirling Numbers", (with G. E. Andrews, E. Egge, W. Gawronski), J. Combinatorial Theory Ser. A, 120(2013), 288303..
 2012
 93) ." Classical and Sobolev orthogonality of the nonclassical Jacobi polynomials with parameters α = β = 1 ", (with A. Bruder), Ann. Mat. Pura Appl., DOI 10.1007/s1023101202848.
 94). "Franciszek Hugon Szafraniec: A Scholar of Eminence" (with D. Cichoń and J. Stochel), Complex Anal. Oper. Theory, 6(2012), no. 3, 529531.
 95). "Quasiseparation of a generalized biharmonic partial differential equation associated with the fourthorder Laguerretype differential equation", (with C. Markett), in preparation.
 2013
 96). " The Spectral Analysis of the X__{1} Laguerre Polynomials", (with M. J. Atia and J. Stewart), Advances in Dynamical Systems and Applications, to appear.
 97). " The Spectral Analysis of the X__{1} Jacobi Polynomials", (with C. Liaw, J. Stewart, and Q. Wicks), in preparation.

``An old classification problem in orthogonal polynomials and consequences of its modern interpretation'', (with W.N. Everitt and K.H. Kwon), in Seminario Avanzado en Teoria de Aproximación (editor: F. Marcellán and J. Vinuesa), Laredo, 1994, 6776.

``Leftdefinite theory of differential operators: on the generalization of the SonineHahn classification theorem for orthogonal polynomials'', (with W.N. Everitt and K.H. Kwon), in Seminario Avanzado en Teoria de Aproximación (editor: F. Marcellán and J. Vinuesa), Laredo, 1994, 7783.

``Some new results and some open problems in the subject of differential equations /orthogonal polynomials'', (with W.N. Everitt and K.H. Kwon), in Seminario Avanzado en Teoria de Aproximación (editor: F. Marcellán and J. Vinuesa), Laredo, 1994, 8487.

``Differential equations and BochnerKrall orthogonal polynomials'', (with A.M. Krall), USU Technical Report, 50 pages.

``Notes on the DPS classification problem and the classification problem'', (with W.N. Everitt), USU Technical Report #56, 28 pages.

``The operator domains for the Legendre differential expression'', (with W.N. Everitt and S.M. Loveland), USU Technical Report #57, 56 pages.

``Classification Problems in Differential Equations and Orthogonal Polynomials'', USU Technical Report #92, 23 pages.

``The Frobenius Program: A User's Guide'', (with B.M. Brown, W.N. Everitt and D.K.R. McCormack). USU Technical Report #94, 28 pages.

``Orthogonal polynomials and spectral theory: a survey (updated version), (with W.N. Everitt).

"Analytic and functional analytic problems in differential equations and orthogonal polynomials", USU Technical Report #116, 19 pages.

"The Frobenius Program: A User's Guide", (with B.M. Brown, W.N. Everitt, and D.K.R. McCormack),30 pages.

``A new set of orthogonal polynomials'', contributed talk, AMS annual meeting, San Francisco, 1980.

``A sixth order differential equation having orthogonal polynomial solutions'', colloquium talk, University of Western Ontario, February, 1981.

``Orthogonal polynomials and differential equations'', colloquium talk, University of Manitoba, April, 1981.

``Weight distributions and moments for a certain class of orthogonal polynomials'', invited talk, Southeastern Differential Equations Conference, North Carolina State University, October, 1982.

``On the classification of differential equations having orthogonal polynomial solutions'', contributed talk, Special Session, AMS annual meeting, Denver, 1983.

``Orthogonal polynomials, weight distributions, and differential equations'', invited lecture, University of Toronto MiniConference on Differential Equations and Orthogonal Polynomials, April, 1983.

``Weight distributions and moments for a certain class of differential equations'', contributed talk, International Conference on Ordinary and Partial Differential Equations, University of Alabama, Birmingham, April, 1983.

``Orthogonal polynomials, weight distributions and differential equations'', colloquium talk, University of Manitoba, April, 1983.

``Orthogonal polynomials, weight distributions and differential equations'', colloquium talk, University of Calgary, April, 1983.

``A survey of recent results on the connections between orthogonal polynomials and differential equations'', invited lecture, AMS meeting, University of Notre Dame, April, 1984.

``Symmetry factors and orthogonal polynomials'', colloquium talk, University of Utah, December, 1985.

``Necessary and sufficient conditions for the existence of symmetry factors for real and ordinary differential expressions'', contributed talk, International Conference on Ordinary and Partial Differential Equations, University of Alabama, Birmingham, March, 1986.

``SturmLiouville operators and orthogonal polynomials'', invited lecture, Canadian Mathematical Society Seminar on Differential Equations, University of Toronto, July, 1986.

``Constructing weight functions for orthogonal polynomials'', invited lecture, Constructive Function Theory Conference, Edmonton, Alberta, July, 1986.

``Ordinary and partial differential equations with orthogonal polynomial eigenfunctions: a unifed theory'', plenary lecture, Second International Conference on Orthogonal Polynomials and their Applications, Segovia, Spain, September, 1986.

``A survey of SturmLiouville equations with orthogonal polynomial solutions'', colloquium talk, University of Birmingham, England, May, 1987.

``A survey of SturmLiouville equations with orthogonal polynomial solutions'', colloquium talk, King's College, Unversity of London, England, May, 1987.

``On the construction of weight functions for a certain class of orthogonal polynomials for a certain class of orthogonal polynomials'', colloquium talk, Oxford Unversity, May, 1987.

``Orthogonal polynomials in Sobolev spaces'', plenary lecture, International Congress of Orthogonal Polynomials and Applications, Laredo, Spain, September, 1987.

``Orthogonal polynomials and right and leftdefinite boundary value problems'', colloquium talk, University of Western Ontario, December, 1987.

``A characterization of formally symmetric differential expressions'', invited lecture, International Conference on Theory and Applications of Differential Equations, Columbus, Ohio, March, 1988.

``On the construction of weight distributions for a certain class of orthogonal polynomials'', colloquium talk, University of Ottawa, March, 1988.

``Leftdefinite boundary value problems and a conjecture of Hahn'', colloquium talk, University of Ottawa, March, 1988.

``On the construction of weight distributions for a certain class of orthogonal polynomials'', colloquium talk, Penn State University, March, 1988.

``A characterization of formally symmetric differential expressions'', contributed lecture, Intermountain Section of Mathematical Association of America, Logan, Utah, April, 1988.

``Constructing weight distributions for a certain class of orthogonal polynomials'', colloquium talk, Idaho State University, January, 1989.

``Symmetric and symmetrisable differential expressions'', invited lecture, International Conference on Differential Equations: Theory and Applications in Stability and Control, Colorado College, Colorado Springs, June, 1989.

``Constructing weight functions for orthogonal polynomials'', colloquium talk, University of Granada, Granada, Spain, September, 1989.

``Constructing weight functions for orthogonal polynomials'', colloquium talk, Polytechnic University of Madrid, Madrid, Spain, September, 1989.

``Spectral differential equations and the theory of singular differential operators'', main address, Spanish National Conference on Orthogonal Polynomials and their Applications, Gijon, Spain, September, 1989.

``The five Legendre differential equations'', main address, Spanish National Conference on Orthogonal Polynomials and their Applications, Gijon, Spain, September, 1989.

``Spectral differential equations and orthogonal polynomials'', colloquium talk, University of South Africa, Pretoria, South Africa, February, 1990.

``Spectral differential equations and orthogonal polynomials'', colloquium talk, The University of the Witwatersrand, Johannesburg, South Africa, February, 1990.

``Constructing weight distributions for a certain class of orthogonal polynomials'', colloquium talk, University of South Africa, Pretoria, South Africa, March, 1990.

``Spectral differential equations and orthogonal polynomials'', colloquium talk, University of Pretoria, Pretoria, South Africa, March, 1990.

``Orthogonal polynomials: a historical lecture'', colloquium talk, University of
Bophuthatswana, Mmabatho, Bophuthatswana, March, 1990. 
``Sobolev orthogonality'', plenary lecture, Inaugural Meeting of Contact Group for Special Functions'', Namur, Belgium, September, 1990.

``Constructing weight functions for a certain class of orthogonal polynomials'', colloquium talk, University of Twente, Enschede, The Netherlands, November, 1990.

``Constructing weight functions for a certain class of orthogonal polynomials'', colloquium talk, University of Groningen, Groningen, The Netherlands, November, 1990.

``Symmetric differential expressions'', invited lecture, Special Meeting on Spectral Theory (organizers: H.D. Niessen, A. Schneider, J. Weidmann), Olberwolfach, Germany, January, 1991.

``A realvalued weight function for the Bessel polynomials'', colloquium talk, University of Aachen, Aachen, Germany, January, 1991.

``Orthogonal polynomials and spectral theory'', colloquium talk, University of Sussex, Brighton, England, February, 1991.

``A realvalued weight function for the Bessel polynomials'', colloquium talk, University of Cambridge, Cambridge, England, February, 1991.

``Differential equations for the generalized Laguerre and Jacobi polynomials'', colloquium talk, The University of Birmingham, Birmingham, England, May, 1991.

``The Bessel moment problem'', plenary lecture, Gregynog Symposium on Pure Mathematics, Gregynog, Wales, May, 1991.

``A survey of leftdefinite spectral theory and Sobolev orthogonal polynomials'', Workshop on Orthogonal Polynomials and Sobolev Spaces, Leganés, Spain, June, 1992.

``A solution to the Bessel moment problem'', colloquium talk, University of Zaragoza, Zaragoza, Spain, June, 1992.

``An old classification problem in orthogonal polynomials and the consequences of its modern interpretation'', plenary lecture, Seminario avanzado en teoría de aproximación, Laredo, Spain, September, 1992.

``Spectral theory of differential operators I: the theory of GlazmanKreinNaimark (rightdefinite theory)'', plenary lecture, Seminario avanzado en teoría de aproximación, Laredo, Spain, September, 1992.

``Spectral theory of differential operators II: the leftdefinite theory of differential operators and the generalization of the SonineHahn classification theorem for orthogonal polynomials'', plenary lecture, Seminario avanzado en teoría de aproximación, Laredo, Spain, September, 1992.

``Some new results and some open problems in the subject of differential equations/
orthogonal polynomials'', plenary lecture, Seminario avanzado en teoría de aproximación, Laredo, Spain, September, 1992. 
``Sobolev orthogonal polynomials and secondorder differential equations'', invited lecture, Gregynog Workshop on Computational Techniques in Spectral Theory and Related Topics, Gregynog, Wales, July, 1993.

``A generalization of Bochner's characterization theorem of the classical orthogonal polynomials'', colloquium lecture, Carleton University, Ottawa, Canada, December, 1993.

``Orthogonal polynomials, leftdefinite boundary value problems and W.N. Everitt'', invited lecture, W.N. Everitt Conference, Tuscaloosa, Alabama, March, 1994.

``Sobolev orthogonal polynomials and secondorder differential equations'', invited lecture, Banach Institute, Warsaw, Poland, March, 1994.

``Recent advances in the spectral theory of the Laguerre polynomials'', invited lecture, Banach Institute, Warsaw, Poland, March, 1994.

``A short course in orthogonal polynomials and their applications'', MAA invitation, MAA Regional Meeting, Westminster College, Salt Lake City, April, 1994.

``Sobolev orthogonal polynomials and a generalization of a theorem of Bochner'', colloquium talk, Andong National University, Andong, South Korea, August, 1996.

``Sobolev orthogonal polynomials and a generalization of a theorem of Bochner'', colloquium talk, KAIST Institute, Taejon, South Korea, August, 1996.

``The GlazmanKreinNaimark Theorem and beyond'', colloquium talk, KAIST Institute, Taejon, South Korea, August, 1996.

``The Laguerre differential equation when is a negative integer: spectral analysis '', colloquium talk, KAIST Institute, Taejon, South Korea, August, 1996.

``Sobolev orthogonal polynomials and a generalization of a theorem of Bochner'', colloquium talk, Sung Kyun Kwan University, Suwon, South Korea, August, 1996.

``Sobolev orthogonal polynomials and a generalization of a theorem of Bochner'', colloquium talk, Changwon National University, ChangWon, South Korea, September, 1996.

``The Laguerre differential equation when is a negative integer: spectral analysis '', colloquium talk, Sung Kyun Kwan University, Suwon, South Korea, September, 1996.

``The Laguerre differential equation when is a negative integer: spectral analysis '', colloquium talk, Seoul National University, Seoul, South Korea, September, 1996.

``The Bessel moment problem: the solution'', colloquium talk, University of Western Ontario, London, Ontario, Canada, December, 1996.

``The spectral analysis of the Laguerre polynomials for positive integers '', invited lecture, Eighth Symposium on Orthogonal Polynomials and their Applications, Seville, Spain, September, 1997.

``Leftdefinite spectral theory with applications to differential equations and orthogonal polynomials'', invited lecture, International Workshop on Special Functions, Hong Kong, June, 1999.

``A general leftdefinite theory with applications to differential equations'', invited lecture, Computation and Analytic Problems in Spectral Theory, Gregynog, Wales, July, 1999.

``Orthogonal polynomials, linear differential equations, and the Kramer sampling theory'', plenary lecture, Fifth International Symposium on Orthogonal Polynomials, Special Functions and their Applications, Patras, Greece, September 1999.

``Leftdefinite spectral theory with applications to orthogonal polynomials'', invited lecture, Fifth International Symposium on Orthogonal Polynomials, Special Functions and their Applications, Patras, Greece, September 1999.

``Henry John Stephen Smith and Fermat's Two Squares Theorem'', colloquium lecture, Carlos III University, Leganés, Spain, October, 1999.

``Leftdefinite spectral theory with applications to orthogonal polynomials'', OPS Seminar Group lecture, Carlos III University, Leganés, Spain, October, 1999.

``Henry John Stephen Smith and Fermat's Two Squares Theorem'', colloquium lecture, University of Valladolid, Valladolid, Spain, February, 2000.

``A general leftdefinite theory of positive selfadjoint operators'', colloquium lecture, University of Valladolid, Valladolid, Spain, February, 2000.

``Two proofs of the EverittMariċ result for the Legendre differential equation'', invited lecture, Advanced Study Institute  NATO conference, Arizona State University, May, 2000.

``The old meets the new: the method of Frobenius and Mathematica'', invited lecture, Advanced Study Institute  NATO conference, Arizona State University, June, 2000.

``The BKS(N,M) problem in orthogonal polynomials and differential equations'', invited lecture, AMS Sectional Meeting, Birmingham, Alabama, November, 2000.

``Leftdefinite spectral theory for a class of positive selfadjoint operators'', colloquium lecture, Utah State University, January, 2001.

``Leftdefinite spectral theory for a class of positive selfadjoint operators'', colloquium lecture, University of Central Florida, February, 2001.

``Stirling numbers, Legendre numbers and orthogonal polynomials'', invited lecture, Sixth International Symposium on Orthogonal Polynomials, Special Functions and Applications, Rome, June, 2001.

``Leftdefinite spectral theory and powers of differential equations, invited lecture, Twentyfirst Annual SoutheasternAtlantic Regional Conference on Differential Equations, Wake Forest University, November, 2001.

``Orthogonal polynomials and differential equations: the Problem'', invited lecture, Carlos III University, Madrid, Spain, March, 2002.

``Orthogonal polynomials and differential operators I: the theory'', invited lecture, Carlos III University, Madrid, Spain, March, 2002.

``Orthogonal polynomials and differential operators II: the LittlejohnWellman leftdefinite theory'', invited lecture, Carlos III University, Madrid, Spain, March, 2002.

``An Example: Legendre's differential equation and Legendre polynomials'', invited lecture, Carlos III University, Madrid, Spain, March, 2002.

``Leftdefinite Spectral Theory, Legendre Polynomials, and LegendreStirling Numbers'', plenary lecture, Tunisian Mathematical Society, Mahdia, Tunisia, March 2002.

``On the construction of weight distributions for polynomials in the classes'', colloquium lecture, University of Gabes, Gabes, Tunisia, March 2002.

``Henry John Stephen Smith and Fermat's Two Squares Theorem'', colloquium lecture, University of Gabes, Gabes, Tunisia, March 2002.

"LeftDefinite Spectral Theory, Orthogonal Polynomials, and Generalized Stirling Numbers", colloquium lecture, Division of Applied Mathematics, KAIST, Daejeon, Korea, July, 2002.

"JacobiStirling numbers and the leftdefinite theory for the classical Jacobi differential equation", invited lecture, 22nd Southeastern Atlantic Regional Conference on Differential Equations, University of Tennessee, Knoxville, October, 2002.

"General leftdefinite theory with applications to selfadjoint differential and difference operators", invited lecture, Bexbach Workshop 2002, Bexbach, Germany, October, 2002.

"Orthogonal polynomials and differential equations: the BKS problem", colloquium lecture, The University of Saskatchewan, Saskatoon, Saskatchewan, Canada, February, 2003.

"Leftdefinite operator theory with applications to special functions", colloquium lecture, The University of Saskatchewan, Saskatoon, Saskatchewan, Canada, February, 2003.

"Rightdefinite differential operators: the GlazmanKreinNaimark theory", colloquium lecture, The University of Saskatchewan, Saskatoon, Saskatchewan, Canada, February, 2003.

"General leftdefinite theory with applications to selfadjoint differential operators and orthogonal polynomials", colloquium lecture, Georgia Tech University, October, 2003.

"Laguerre polynomials and selfadjoint operators", colloquium lecture, Georgia Tech University, October, 2003.

"An introduction to leftdefinite theory", Workshop in Difference Equations and Special Functions, Invited Lecture, Otocec, Slovenia, October, 2003.

"An integral inequality and Legendre's differential equation", Workshop in Difference Equations and Special Functions, Invited Lecture, Otocec, Slovenia, October, 2003.

"Laguerre polynomials and selfadjoint operators", colloquium lecture, Technical University of Munich, Germany, October, 2003.

"Some applications of leftdefinite theory for positive selfadjoint operators", invited lecture, Mfunction and Related Topics Conference (in honor of W. N. Everitt), Cardiff, Wales, July, 2004.

"Regular Right and Left Definite Boundary Value Problems with Applications to Fourier Analysis", ABiTUMath Workshop, Invited Lecture, Munich, Germany and Novacella, Italy, October, 2004.

"Abstract LeftDefinite Theory for Positive SelfAdjoint Operators", invited lecture, special session on Spectral Problems of Differential Operators, American Mathematical Society meeting, Northwestern University, Evanston, Illinois, October, 2004.

"A Simple Proof of Fermat's Theorem  No, Not That One!", invited lecture, AbiTUMath Workshop, Munich, Germany and Novacella, Italy, March/April, 2005.

"An Introduction to LeftDefinite Theory", invited lecture, Workshop on Sampling, Spectral Theory, and their Applications, University of West Georgia, April, 2005.

"Applications of LeftDefinite Theory to Classical Orthogonal Polynomials and Combinatorics", invited lecture, Workshop on Sampling, Spectral Theory, and their Applications, University of West Georgia, April, 2005.

"LaguerreSobolev Polynomials: Their Orthogonality and Applications to Sampling Theory", invited lecture, Workshop on Sampling, Spectral Theory, and their Applications, University of West Georgia, April, 2005.

"Leftdefinite operator theory with applications to orthogonal polynomials and combinatorics", colloquium lecture, Baylor University, April, 2005.

"Leftdefinite theory with applications to orthogonal polynomials", colloquium lecture, University of MissouriRolla, May, 2005.

"LagrangeSobolev adjoints and LagrangeSobolev symmetry of ordinary differential expressions", contributed talk, Southeastern Atlantic Regional Conference on Differential Equations, University of North Carolina  Greensboro, October, 2006"

"LagrangeSobolev Adjoints, Symmetry, and Orthogonal Polynomials", colloquium talk, Baylor University, November, 2006.

"Orthgonal Polynomials and LeftDefinite Spectral Theory", invited lecture, 1027th AMS Regional Meeting, Tucson, Arizona, April, 2007.

"LagrangeSobolev Adjoints and LagrangeSobolev Symmetry of Ordinary Differential Expressions", invited lecture, 1027th AMS Regional Meeting, Tucson, Arizona, April, 2007.

"LeftDefinite Spectral Theory with Applications to Orthogonal Polynomials", plenary lecture, Special Functions, Information Theory and Mathematical Physics, An Interdisciplinary Conference in Honor of Jesus S. Dehesa's 60th birthday, Granada, Spain, September, 2007.

"LeftDefinite Operator Theory", plenary lecture, Palestinian Conference on Modern Trends in Mathematics and Physics, Birzeit University, Birzeit, Palestine, July, 2008.
"Leftdefinite spectral theory with applications to combinatorics", colloquium lecture, Texas A&M University, October, 2008.
"Stieltjes ghost functions and the Bessel moment problem", colloquim lecture, Trinity University, January, 2009.
"LegendreStirling Numbers", contributed talk, 10th International Symposium on Orthogonal Polynomials, Special Functions and their Applications, Leuven, Belgium, July, 2009.
"The Influence of W. N. Everitt on Differential Operators and Orthogonal Polynomials", invited lecture, W. N. Everitt Retirement Conference, University of Birmingham, England, September, 2009.
"Legendre polynomials, LegendreStirling numbers, and leftdefinite operator theory", invited lecture, Department of Mathematics, University of North Texas, November, 2009.
"Bessel's equation and a generalization of Hardy's inequality", plenary lecture, Functions and Operators 2010, Kraków, Poland, June, 2010.

"Applications of leftdefinite operator theory to orthogonal polynomials and integral inequalities", colloquium talk, Texas A&M University, October, 2010.
"A generalization of Hardy's inequality", colloquium lecture, University of Birmingham, England, June, 2011.
"The LegendreStirling Numbers", invited lecture, Workshop on Analytic and Computational Techniques in Spectral Theory and Related Topics, EPSRC Gregynog Workshop 2011, June, 2011.

"A New Result in Old Mathematics: Variation of Parameters and Solutions of Linear Differential Equations", colloquium lecture, University of Trier, Germany, July, 2012.

"Spectral Analysis of the X_{1} Laguerre Polynomials", invited lecture, International Conference on Differential Equations, Difference Equations, and Special Functions, Patras, Greece, September, 2012.

"Legendre polynomials, LegendreStirling numbers, and leftdefinite operator theory " Colloquium Lecture, Texas Christiann University, October, 2012.

Susan Marie Loveland, Spectral analysis of the Legendre Equations, Ph.D., May, 1990, Utah State University.

Richard Wellman, Selfadjoint representations of a certain sequence of spectral differential equations, Ph.D., June, 1995, Utah State University.

Andrea Bruder, Applied leftdefinite theory: the Jacobi polynomials, their Sobolev orthogonality, and selfadjoint operators, Ph.D., May, 2009, Baylor University. .

Davut Tuncer, The leftdefinite spectral analysis of the Legendre type differential equation, Ph.D., December, 2009, Baylor University..

Jessica Stewart, current Ph.D. student.
Quinn Wicks, current Ph.D. student.

S. Mashike, South Africa, February, 1990, MorseSturm Variational Theory for Systems of nonregular selfadjoint fourthorder differential equations.

S. Belmehdi, France, September, 1990, Formes lineaires et polynomes orthogonaux semiclassiques de classes Description et classification.

R. Koekoek, The Netherlands, November, 1990, Generalizations of the classical Laguerre polynomials and some qanalogues.

A. Kroopnick, South Africa, July, 1991, Boundedness, oscillation, and stability theorems for certain classes of second order differential equations.
Technical Reports:
Lectures:
Graduate Students:
External Chairman of Foreign Students:
Grants:
1984  Utah State University Summer Research Grant (funded) 
1985  Utah State University Summer Research Grant (funded) 
1986  Utah State University Summer Research Grant (funded) 
1989  Science and Engineering Research Council (England) Grant (funded) 
1999  Ministry of Education (Spain) (funded; SAB19980098) 
1999  National Science Foundation ($56K; funded; DMS9970478 ) 
2001  National Science Foundation ($6K; funded; DMS9970478) 
2003  Banff International Research Station ($15K; for conference in March 2004) 
Awards and Honors:
1973  University of Western Ontario (UWO) Statistics Scholarship 
1975  Annie R. Kingston Gold Medal for Mathematics (UWO) 
19761979  National Research Council Postgraduate Scholarship 
19801981  National Science and Engineering Research Council Scholarship 
1981  Hoover Teaching Award, The Pennsylvania State University 
1990  College of Science Teacher of the Year (Utah State University) 
1992  International Professor of the Year (Utah State University) 
1994  MAA Intermountain Section Distinguished Teaching Award 
2005  Mortar Board Top Professor Award 
Professional Memberships:
Canadian Mathematical Society 
Mathematical Association of America 
Society for Industrial and Applied Mathematics 
American Mathematical Society 
London Mathematical Society 
South African Mathematical Society 
Korean Mathematical Society 
Other Professional Activities:
Editorial Board: Advances in Dynamical Systems and Applications,
Abstract and Applied Analysis
Reviewer: Mathematical Reviews, Zentralblatt
Referee: Abstract and Applied Analysis, Advances in Dynamical Systems
and Applications, Quaestiones Mathematicae, Journal of Constructive
Approximation, SIAM Journal of Mathematical Analysis, Results in Mathematics,
Applicable Analysis, Proceedings of London Mathematical Society, Journal of
Mathematical Analysis and Applications, Proceedings of Royal Society of
Edinburgh, Journal of Approximation Theory, The American Mathematical Monthly,
Journal of Computational and Applied Mathematics, Transactions of the American
Mathematical Society, Rocky Mountain Journal of Mathematics, Applied Numerical
Mathematics, Annals of Numerical Mathematics, National Science Foundation,
Proceedings of the American Mathematical Society, Studia Mathematica, Applied
Mathematics Letters, Methods and Applications of Analysis
Guest Editor: Rocky Mountain Journal of Mathematics, Journal of
Computational and Applied Mathematics
Board of Directors: Canadian Mathematical Society (19931997)
Chairman: Intermountain Section of the MAA (19961998)
American Mathematical Society: Professional Ethics Subcommittee (20072009)
Seminars Taught:
Approximation Theory (UTSA and USU) 
Banach Algebras (USU) 
Orthogonal Polynomials (USU) 
Unbounded Operators (USU) 
Singular differential operators (USU) 
Spectral Theory and Orthogonal Polynomials (University of Wales) 
Spectral Theory of Differential Operators with Applications to 
Orthogonal Polynomials (Carlos III University, Spain) 
Courses Taught:
Undergraduate: college algebra, precalculus, trigonometry, calculus,
multivariable calculus, linear algebra, differential equations, partial
differential equations, engineering analysis, topology, complex variables,
modern algebra, numerical analysis, real analysis, number theory.
Graduate: ordinary differential equations, linear algebra, real
variables, measure theory, Fourier analysis, orthogonal polynomials, topology,
functional analysis, numerical analysis, approximation theory, special
functions, Banach algebras, modern algebra.
Last updated: July 28, 2013