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arXiv · 0903.5073

More refined enumerations of alternating sign matrices

Ilse Fischer·Dan Romik
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Abstract

We study a further refinement of the standard refined enumeration of alternating sign matrices (ASMs) according to their first two rows instead of just the first row, and more general "d-refined" enumerations of ASMs according to the first d rows. For the doubly-refined case of d=2, we derive a system of linear equations satisfied by the doubly-refined enumeration numbers A_{n,i,j} that enumerate such matrices. We give a conjectural explicit formula for A_{n,i,j} and formulate several other conjectures about the sufficiency of the linear equations to determine the A_{n,i,j}'s and about an extension of the linear equations to the general d-refined enumerations.

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Ilse Fischer, Dan Romik. 2009-04-15. More refined enumerations of alternating sign matrices. https://arxiv.org/abs/0903.5073

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