Abstract
A signed inversion sequence of length n is a sequence of integers (Formula Present), where (Formula Present) for every i ∈ {0, 1, …, n − 1}. For a set of signed patterns B, let Īn(B) be the set of signed inversion sequences of length n that avoid all the signed patterns from B. We say that two sets of signed patterns B and C are Wilf-equivalent if |Īn(B)| = |Īn(C)| for every n ≥ 0. In this paper, by generating trees, we show that the number of Wilf-equivalences among singles of a length-2 signed pattern is 3 and the number of Wilf-equivalences among pairs of a length-2 signed patterns is 30.
Original language | English |
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Pages (from-to) | 13-20 |
Number of pages | 8 |
Journal | Discrete Mathematics Letters |
Volume | 14 |
DOIs | |
State | Published - 2024 |
Bibliographical note
Publisher Copyright:© 2024 the authors.
Keywords
- generating trees
- inversion sequences
- signed inversion sequences
- Wilf-equivalences
ASJC Scopus subject areas
- Discrete Mathematics and Combinatorics