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arXiv · 2512.09420

Factorisability in K-theory

Jørgen Vold Rennemo
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Abstract

We revisit and give a detailed proof of a lemma of Okounkov showing that, for a scheme X with a torus action, the Euler characteristic generating function associated with a "factorisable" sequence of torus-equivariant coherent sheaves on the symmetric powers $\operatorname{Sym}^n X$ equals the plethystic exponential of the generating function of Euler characteristics of some sequence of sheaves on X.

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Jørgen Vold Rennemo. 2025-12-10. Factorisability in K-theory. https://arxiv.org/abs/2512.09420

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