Professor of Mathematics
University of Pennsylvania

CAGE (Combinatorics, Algebra, and Geometry) Seminar

Penn Colloquium 2017-18

My research interests are in algebraic and enumerative combinatorics. In particular, I work on problems involving symmetric functions and Macdonald polynomials, combinatorial statistics and q-analogs, rook polynomials, and am also interested in the zeros of polynomials and analytic functions. I like experimental mathematics, and often use computer algebra packages such as Maple in my research, to develop and test conjectures.


  • Publications and Preprints,


  • The q,t-Catalan Numbers and the Space of Diagonal Harmonics in pdf format or ps format

    The official bound version of this book can be ordered from the AMS. It is part of the AMS University Lecture Series.


    Spring 2018

  • AMCS 603 (Applied Algebra)


  • PhD and Masters Students

  • Postdoctoral

    Upcoming Presentations and Conferences

  • Workshop on Equivariant Combinatorics, CRM, Montréal, Canada, June 19-23, 2017.

  • The 29th International Conference on Formal Power Series and Algebraic Combinatorics (FPSAC), London, United Kingdom, July 9-13, 2017.

  • Special Session on Polynomials in Enumerative, Algebraic, and Geometric Combinatorics, Fall Eastern Sectional Meeting, SUNY Buffalo, Buffalo, NY, September 16-17, 2017.

  • Workshop on Enumerative Combinatorics (part of the program "Algorithmic and Enumerative Combinatorics"), Erwin Schrödinger Institute (ESI), University of Vienna, Vienna, Austria, October 16-20, 2017.

  • Algebra, Combinatorics and Geometry seminar, University of Pittsburgh, February 22, 2018.

  • Special Session on Macdonald Polynomials and Related Structures, Spring Southeastern Sectional Meeting, Vanderbilt University, Memphis, TN, April 14-15, 2018.

  • MFO Workshop on Enumerative Combinatorics, Oberwolfach, Germany, May 13-19, 2018

  • BIRS Workshop on Hessenberg Varieties in Combinatorics, Geometry, and Representation Theory, Banff, CA Oct. 21-26, 2018

    Some Past Workshops

  • BIRS Workshop on Applications of Macdonald Polynomials, September 9-14, 2007

  • Oberwolfach Workshop on Combinatorial Representation Theory, March 22-27, 2010

  • BIRS Workshop on Quasisymmetric Functions, November 14-19, 2010

  • MFO Workshop on Enumerative Combinatorics, Oberwolfach, Germany, March 2-8, 2014

    Transparencies from Selected Presentations

  • The (q,t)-Catalan Numbers and the Space of Diagonal Harmonics, hour long Invited Address, AMS Sectional, Orlando Fl. Nov. 9, 2002.

  • A Combinatorial Model for the Macdonald Polynomials (in pdf format), or postscript format, hour long presentation at the Workshop on Resolutions, Inverse Systems, and Coinvariants, University of Ottawa, Jan. 13, 2005.

  • Recent Combinatorial Results involving Macdonald Polynomials and Diagonal Harmonics (in postscript format), or pdf format, Plenary Address at the 18th International Conference on Formal Power Series and Algebraic Combinatorics (FPSAC '06), San Diego, CA, June 22, 2006.

  • The Monotone Column Permanent Conjecture and Multivariate Eulerian Polynomials , hour long presentation at the 26th Clemson mini-Conference on Discrete Mathematics and Algorithms, Clemson University, Oct. 28, 2011.

    The PhD Oral Exam in Combinatorics at Penn

    Editorial Boards

  • Transactions of the AMS

  • Journal of Combinatorics

  • Bulletin of Parana's Mathematical Society

  • Involve


  • Member of the AMS and MAA

  • Fellow of the AMS

    Department of Mathematics
    University of Pennsylvania
    209 South 33rd St.
    David Rittenhouse Laboratory
    Philadelphia, PA 19104-6395
    Phone: 215-573-9093
    Fax: 215-573-4063
    email: jhaglundATmath.upenn.edu