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arXiv · 1605.05806

Kostka-Shoji polynomials and Lusztig's convolution diagram

Michael Finkelberg·Andrei Ionov
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Abstract

We propose an $r$-variable version of Kostka-Shoji polynomials $K^-_{λμ}$ for $r$-multipartitions $λ,μ$. Our version has positive integral coefficients and encodes the graded multiplicities in the space of global sections of a line bundle over Lusztig's iterated convolution diagram for the cyclic quiver $\tilde{A}_{r-1}$.

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Michael Finkelberg, Andrei Ionov. 2017-11-08. Kostka-Shoji polynomials and Lusztig's convolution diagram. https://arxiv.org/abs/1605.05806

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