Harry Richman

I am interested in problems in combinatorics, tropical geometry, and number theory.

I was recently a postdoc at the University of Washington where my mentor was Farbod Shokrieh. Before that I was a graduate student at the University of Michigan where my advisors were David Speyer and Jeff Lagarias. I was on the job market in fall 2019.

Before graduate school I studied math at MIT and the Math in Moscow program.


email: hrichman (at) alum (dot) mit (dot) edu


Spring 2022: Math 208
Winter 2022: Math 208
Winter 2022: WXML Counting spanning trees
Autumn 2021: WXML Counting spanning trees
Summer 2021: MREG Rational Catalan combinatorics
Spring 2021: Math 308
Autumn 2020: Math 308 (linear algebra)
Winter 2019: Math 116, Origami on Lattices
Winter 2018: Math 116
Fall 2016: Math 215 (multivariable calculus)
Winter 2016: Math 116
Fall 2015: Math 216 (differential equations)
Winter 2015: Math 116 (calculus II)
Fall 2014: Math 115 (calculus I)


  1. "Dilated floor functions that commute," coauthored with J. C. Lagarias and T. Murayama. American Math. Monthly 123.10 (2016), pp. 1033-1038.
    arXiv:1611.05513. DOI: 10.4169/amer.math.monthly.123.10.1033.

  2. "Dilated floor functions having nonnegative commutator I. Positive and mixed sign dilations," coauthored with Jeffrey Lagarias. Acta Arithmetica 187.3 (2019), pp. 271-299.
    arXiv:1806.00579. DOI: 10.4064/aa180602-21-9.

  3. "Dilated floor functions having nonnegative commutator II. Negative dilations," coauthored with Jeffrey Lagarias. Acta Arithmetica 196.2 (2020), pp. 163-186.
    arXiv:1907.09641. DOI: 10.4064/aa190628-14-1.

  4. "The distribution of Weierstrass points on a tropical curve," submitted.

  5. "Derangements and the p-adic incomplete gamma function," coauthored with Andrew O'Desky, accepted for publication in the Transactions of the American Mathematical Society.
    arXiv:2012.04615. DOI: 10.1090/tran/7357.

  6. "Counting tripods on the torus," coauthored with Jayadev S. Athreya and David Aulicino, accepted for publication in the Arnold Mathematical Journal.
    arXiv:2111.01891. DOI: 10.1007/s40598-022-00216-z.

  7. "The tropical Manin-Mumford conjecture," submitted.

  8. "The floor quotient partial order," coauthored with Jeffrey Lagarias, in preparation.

  9. "Origami hexagon deformations and the flip graph," coauthored with Y. Liu, in preparation.

Notes and Presentations


Analysis quals
Rubik's cube
Quotes about math
Origami simulator built by Amanda Ghassaei
Multiline formulas guidelines provided by Acta Arithmetica
Math Subject Classification browse and search, resource from zbMATH
OEIS Online Encyclopedia of Integer Sequences
Why should I do math? Reasons by Tao Lin (43., 35., 31., 10., 28., 8., 11., 14., 41., 26., 21., 18.)