Abstract
Making use of a combinatorial approach, we prove two refined major-balance identities on the 321-avoiding involutions in Sn, respecting the number of fixed points and the number of descents, respectively. The former one is proved in terms of ordered trees whose non-root nodes have exactly two children, and the latter one is proved in terms of lattice paths within a ⌊n2⌋×⌈n2⌉ rectangle.
| Original language | English |
|---|---|
| Pages (from-to) | 250-264 |
| Number of pages | 15 |
| Journal | European Journal of Combinatorics |
| Volume | 49 |
| DOIs | |
| Publication status | Published - 2015 Oct 1 |
ASJC Scopus subject areas
- Discrete Mathematics and Combinatorics