3 papers
math.CO2020
Plethysms and operads
Alex Cebrian
We introduce the -construction, an endofunctor on the category of generalized operads as a general mechanism by which various notions of plethystic substitution arise…
math.CO2019
Combinatorics and simplicial groupoids
Alex Cebrian
This expository paper starts with a brief survey on the relation between partitions and surjections of sets, and then gives a quick introduction to the theories of incidence algebr…
math.CO2018
A simplicial groupoid for plethysm
Alex Cebrian
We give a simple combinatorial model for plethysm. Precisely, the bialgebra dual to plethystic substitution is realised as the homotopy cardinality of the incidence bialgebra of an…