Abstract
In this paper, we identify all members of the (4,4)-Wilf equivalence class for ascent sequences corresponding to the Catalan number Cn = 1/n+1(2n/n). This extends recent work concerning avoidance of a single pattern and pro-vides apparently new combinatorial interpretations for Cn. In several cases, the subset of the class consisting of those members having exactly m ascents is given by the Narayana number Nn,m+1 = 1/n(n/m+1)(n/m). We conclude by considering a further refinement in the case of avoiding 021.
| Original language | American English |
|---|---|
| Pages (from-to) | 288-303 |
| Number of pages | 16 |
| Journal | Applicable Analysis and Discrete Mathematics |
| Volume | 8 |
| Issue number | 2 |
| DOIs | |
| State | Published - 2014 |
Keywords
- Ascent sequence
- Catalan number
- Kernel method
- Narayana number
All Science Journal Classification (ASJC) codes
- Analysis
- Discrete Mathematics and Combinatorics
- Applied Mathematics