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A formula for non-equioriented quiver orbits of type A

A. S. Buch·R. Rimanyi
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Abstract

We prove a positive combinatorial formula for the equivariant class of an orbit closure in the space of representations of an arbitrary quiver of type $A$. Our formula expresses this class as a sum of products of Schubert polynomials indexed by a generalization of the minimal lace diagrams of Knutson, Miller, and Shimozono. The proof is based on the interpolation method of Fehér and Rimányi. We also conjecture a more general formula for the equivariant Grothendieck class of an orbit closure.

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A. S. Buch, R. Rimanyi. 2006-01-19. A formula for non-equioriented quiver orbits of type A. https://arxiv.org/abs/math/0412073

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