## Abstract

An inversion sequence of length n is a sequence of integers e = e_{1} · · · e_{n} which satisfies for each i ∈ [n] = {1, 2, …, n} the inequality 0 >e_{i} < i. For a set of patterns P, we let I_{n} (P) denote the set of inversion sequences of length n that avoid all the patterns from P. We say that two sets of patterns P and Q are IWilf-equivalent if |I_{n} (P)| = |I_{n} (Q)| for every n. In this paper, we show that the number of I-Wilf-equivalence classes among triples of length-3 patterns is 137, 138 or 139. In particular, to show that this number is exactly 137, it remains to prove {101, 102, 110}^{I}∼ {021, 100, 101} and {100, 110, 201}^{I}∼ {100, 120, 210}. Mathematics Subject Classifications: 05A05, 05A15.

Original language | English |
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Article number | P3.19 |

Journal | Electronic Journal of Combinatorics |

Volume | 30 |

Issue number | 3 |

DOIs | |

State | Published - 2023 |

### Bibliographical note

Publisher Copyright:© The authors.

## ASJC Scopus subject areas

- Theoretical Computer Science
- Geometry and Topology
- Discrete Mathematics and Combinatorics
- Computational Theory and Mathematics
- Applied Mathematics