Proof of Stasinski and Voll’s hyperoctahedral group conjecture. (English) Zbl 1406.05010

Landesman, Aaron

Australas. J. Comb. 71, Part 2, 196-240 (2018).

Summary: In a recent paper, A. Stasinski and C. Voll [Electron. J. Comb. 20, No. 3, Research Paper P50, 23 p. (2013; Zbl 1295.05038)] introduced a length-like statistic on hyperoctahedral groups and conjectured a product formula for this statistic’s signed distribution over arbitrary quotients. Stasinski and Voll [loc. cit.] proved this conjecture for a few special types of quotients. We prove this conjecture in full, showing it holds for all quotients. In the case of signed permutations with at most one descent, this formula gives the Poincaré polynomials for the varieties of symmetric matrices of a fixed rank.

MSC:

05A15	Exact enumeration problems, generating functions
05A05	Permutations, words, matrices
05E15	Combinatorial aspects of groups and algebras (MSC2010)
11M41	Other Dirichlet series and zeta functions

Keywords:

Poincaré polynomials; hyperoctahedral groups; signed permutations

References:

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