2020/04/08 by Myers, David Jaz, Spivak, David I.
#18A22 #18B25 #Category Theory (math.CT) #FOS: Mathematics
paper · doi:10.48550/arxiv.2004.04183
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.