Associate Professor, Associate Chair

Greg graduated from Princeton University in 1995 with a BA in Mathematics. Following a year as a computer-game programmer in California, he earned his PhD in Mathematics from Harvard University in 2001 under the supervision of Sara Billey. He was a postdoc at the University of Massachusetts at Amherst and an NSF postdoc at the University of Pennsylvania. After a several years in a tenure-track position at Wake Forest University in North Carolina, he returned to the northeast in 2009 to start at UVM.

Greg is an algebraic combinatorialist: He is interested in understanding the combinatorial scaffolding that underlies rich structures in algebra and geometry. Much of his work relates to the symmetric group of permutations (i.e., orderings), one of the most fundamental objects in mathematics. He is intrigued by simple mathematical problems that arise naturally. This has led to published work on the mathematics of juggling and of the game Memory. In recent years he has been drawn into the mathematics of gerrymandering. His research has been supported by the National Science Foundation, the National Security Agency and the Simons Foundation.


Quantifying gerrymandering using the vote distribution, GS Warrington,
Election Law Journal 17 (1), 39-57, 2018.

Rational parking functions and Catalan numbers, D Armstrong, NA Loehr, GS Warrington, Annals of Combinatorics 20 (1), 21-58, 2016.

What to expect in a game of memory, DJ Velleman, GS Warrington, The American Mathematical Monthly 120 (9), 787-805, 2013.

Juggling probabilities, GS Warrington, The American Mathematical Monthly 112 (2), 105-118, 2005.

Kazhdan-Lusztig polynomials for 321-hexagon-avoiding permutations, SC Billey, GS Warrington, J. of Alg. Comb. 13 (2), 111-136 2001.

Areas of Expertise and/or Research

Algebraic combinatorics, mathematics of gerrymandering


  • PhD, Mathematics - Harvard University
  • BA, Mathematics - Princeton University


  • (802) 656-2195
Office Location:

107 Mansfield

  1. Greg's Website

Courses Taught

  • Math 121 - Calculus III
  • Math 124 - Linear Algebra
  • Math 151 - Groups and Rings
  • Math 173 - Basic Combinatorial Theory
  • Math 251 - Abstract Algebra I
  • Math 273 - Graph Theory
  • Math 295 - Differential Geometry
  • Math 373 - Topics in Combinatorics