School of Mathematical Sciences

Pattern avoidance in permutations menu

Pattern avoidance in permutations

Vladimir Dotsenko (Dublin and Newton Institute)
Mon, 04/02/2013 - 16:30
Seminar series: 

A permutation w is said to contain another permutation w' as a (consecutive) pattern if there is a subword of w that is order-isomorphic to w', otherwise w is said to avoid w'. Enumeration of permutations avoiding a given set of patterns is a challenging combinatorial question. I shall explain an approach to enumeration questions of that sort which is motivated by homological algebra for shuffle algebras (graded vector spaces which are monoids with respect to a certain unconventional monoidal category structure). The talk is supposed to be rather elementary, though an algebraic mind would help to unravel motivations behind it.

Speaker's webpage