Tuesday, March 27, 15:15, 7.527
Judith Marquardt (Bonn), Shod Nakayama algebras and pattern avoiding
permutations
Abstract:
Algebras of small homological dimension, also called shod algebras, have
recently been understood to be a generalisation of tilted algebras via
silting theory. In an attempt to understand this class of algebras better,
we study the class of Nakayama algebras and give a combinatorial
classification when these are shod. We can restrict to linear Nakayama
algebras which are in bijection with Dyck paths. Krattenthaler showed that
these are again in bijection with 132-avoiding permutations. Pattern
avoidance is a classical combinatorial problem which has links to many other
fields. We give a combinatorial classification of Nakayama algebras of small
homological dimension using the Krattenthaler bijection. Namely, we show
that this bijection restricts to a bijection between shod Nakayama algebras
and 132-avoiding permutations which additionally avoid certain other
patterns.