# ALGEBRAIC COMBINATORICS

Skew hook formula for $d$-complete posets via equivariant $K$-theory
Algebraic Combinatorics, Volume 2 (2019) no. 4, pp. 541-571.

Peterson and Proctor obtained a formula which expresses the multivariate generating function for $P$-partitions on a $d$-complete poset $P$ as a product in terms of hooks in $P$. In this paper, we give a skew generalization of Peterson–Proctor’s hook formula, i.e. a formula for the generating function of $\left(P\setminus F\right)$-partitions for a $d$-complete poset $P$ and an order filter $F$ of $P$, by using the notion of excited diagrams. Our proof uses the Billey-type formula and the Chevalley-type formula in the equivariant $K$-theory of Kac–Moody partial flag varieties. This generalization provides an alternate proof of Peterson–Proctor’s hook formula. As the equivariant cohomology version, we derive a skew generalization of a combinatorial reformulation of Nakada’s colored hook formula for roots.

Revised: 2018-12-06
Accepted: 2018-12-15
Published online: 2019-08-01
DOI: https://doi.org/10.5802/alco.54
Classification: 05A15,  06A07,  14N15,  19L47
Keywords: $d$-complete posets, hook formulas, $P$-partitions, Schubert calculus, equivariant $K$-theory
@article{ALCO_2019__2_4_541_0,
author = {Naruse, Hiroshi and Okada, Soichi},
title = {Skew hook formula for $d$-complete posets via equivariant $K$-theory},
journal = {Algebraic Combinatorics},
publisher = {MathOA foundation},
volume = {2},
number = {4},
year = {2019},
pages = {541-571},
doi = {10.5802/alco.54},
mrnumber = {3997510},
zbl = {1417.05011},
language = {en},
url = {alco.centre-mersenne.org/item/ALCO_2019__2_4_541_0/}
}
Naruse, Hiroshi; Okada, Soichi. Skew hook formula for $d$-complete posets via equivariant $K$-theory. Algebraic Combinatorics, Volume 2 (2019) no. 4, pp. 541-571. doi : 10.5802/alco.54. https://alco.centre-mersenne.org/item/ALCO_2019__2_4_541_0/

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