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arXiv · 2004.04183

Dirichlet Functors are Contravariant Polynomial Functors

David Jaz Myers·David I. Spivak
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Abstract

Polynomial functors are sums of covariant representable functors from the category of sets to itself. They have a robust theory with many applications -- from operads and opetopes to combinatorial species. In this paper, we define a contravariant analogue of polynomial functors: Dirichlet functors. We develop the basic theory of Dirichlet functors, and relate them to their covariant analogues.

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David Jaz Myers, David I. Spivak. 2020-04-08. Dirichlet Functors are Contravariant Polynomial Functors. https://arxiv.org/abs/2004.04183

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