Obstructions to combinatorial formulas for plethysm

Thomas Kahle, Mateusz Michalek

Published 2015-07-25Version 1

Motivated by questions of Mulmuley and Stanley we investigate quasi-polynomials arising in formulas for plethysm. We demonstrate, on $S^3(S^k)$, that these need not be counting functions of lattice points in convex bodies, even when restricted to single rays.