A bijection for switching all crossing and nesting numbers for a subclass of matchings, set partitions, and permutations.

Speaker: Lily Yen
Date: 19/07/2012
Time: 13:30 - 15:00

Location: RISC Seminar room

For a subclass of matchings, set partitions, and permutations, we describe a direct bijection involving only arc annotated diagrams that not only interchanges maximum nesting and crossing numbers, but also all refinements of crossing and nesting numbers. Furthermore, we show that the bijection cannot be extended to a larger class of arc annotated diagrams.