English

Permutations all of whose patterns of a given length are distinct

Combinatorics 2012-06-12 v2

Abstract

For each integer k >= 2, let F(k) denote the largest n for which there exists a permutation \sigma \in S_n, all of whose patterns of length k are distinct. We prove that F(k) = k + \lfloor \sqrt{2k-3} \rfloor + e_k, where e_k \in {-1,0} for every k. Suggestions for further investigations along these lines are discussed.

Keywords

Cite

@article{arxiv.1206.0966,
  title  = {Permutations all of whose patterns of a given length are distinct},
  author = {Peter Hegarty},
  journal= {arXiv preprint arXiv:1206.0966},
  year   = {2012}
}

Comments

9 pages, no figures. This is Version 2: A small error at the very end of the proof in Section 2 has been corrected

R2 v1 2026-06-21T21:14:33.393Z