**Contact Information:**

Department of Mathematics

Baylor University

One Bear Place #97328

Waco, TX 76798-7328

**Office**: Sid Richardson 316B

Link to office hours listings

**Phone**: (254) 710-3165

**FAX**: (254) 710-3569

**Personal Website**

**Professor and Chair, Department of Mathematics**

**Associate Dean for Research, Graduate School**

**Education: **

Ph.D., The Pennsylvania State University, 1981

M.A., University of Western Ontario, 1976

B.Sc., University of Western Ontario, 1975

**Biography:**

Dr. Littlejohn joined the Baylor faculty as the Chair of the Mathematics Department in January, 2007. Prior to coming to Baylor he taught at Utah State University (1983-2006) and the University of Texas at San Antonio (1981-1983). He obtained his B.Sc. and M.S. degrees in mathematics from the University of Western Ontario before earning his Ph.D. at Penn State University. He has traveled extensively throughout the world and, in particular, frequently to work with colleagues in various places in the United Kingdom, Spain, and Korea. His hobbies include listening to music, playing squash, and watching/listening to baseball games played by his favorite team, the Detroit Tigers.

**Academic Interests and Research:**

Dr. Littlejohn's research areas include spectral theory of differential operators and special functions. When not working on research problems, he loves to study mathematics in other subjects (especially number theory) and to read popular books on mathematics and on various mathematicians.

**Recent Selected Publications:**

*On the spectra of left-definite operators*, (with R. Wellman), Complex Anal. Oper. Theory, 7(2) (2013), 437-455.

*The Jacobi-Stirling Numbers*, (wtih G. E. Andrews, E. Egge, and W. Gawronski), J. Combinatorial Theory Ser. A, 120 (2013), 288-303.

*Factorization of second-order linear differential equations and Liouville-Neumann expansions*, (with E. García, J. L. López, and E. Pérez Sinusía), Mathematical and Computer Modelling, 57 (2013), 1514-1530.

*Classical and Sobolev orthogonality of the nonclassical Jacobi polynomials with parameters α=β=-1*, (with A. Bruder), Ann. Mat. Pura Appl., DOI 10.1007/s10231-012-0284-8.

*Non-classical Jacobi polynomials and Sobolev orthogonality*, (with A. Bruder), Results Math., 61 (2012), no. 3-4, 283-313.

*The Legendre-Stirling Numbers*, (with G. E. Andrews and W. Gawronski), Discrete Math., 311(2011), 1255-1272.

*The Legendre equation and its self-adjoint operators*, (with A. Zettl), Electron. J. Diff. Equ., Vol. 2011(2011), No. 69, pp. 1-33.

**Recent Lectures:**

*Legendre polynomials, Legendre-Stirling numbers, and left-definite operator theory*, colloqiuim lecture, Texas Christian University, October 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.

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

*The Legendre-Stirling Numbers"*, invited lecture, Workshop on Analytic and Computational Techniques in Spectral Theory and Related Topics, EPSRC Gregynog Workshop 2011, June 2011.

*A Generalization of Hardy's Inequality*, colloquium lecture, University of Birmingham, Birmingham, England, June 2011.

**Current Ph.D. Students:**

Quinn Wicks, Baylor University

Katie Elliott, Baylor University

**Former Ph.D. Students:**

Susan Loveland, Utah State University, 1990

Richard Wellman, Utah State University, 1995

Andrea Bruder, Baylor University, 2009

Davut Tuncer, Baylor University, 2009

Jessica Stewart, Baylor University, 2014

**Some Courses Taught at Baylor:**

- MTH 1321, MTH 1322 - Calculus I, II
- MTH 2311 - Linear Algebra
- MTH 3323 - Introduction to Real Analysis
- MTH 3325 - Ordinary Differential Equations
- MTH 3326 - Partial Diff Equations
- MTH 6V23 - Functional Analysis
- MTH 5323-24 - Real Analysis