English

Positive $m$-divisible non-crossing partitions and their Kreweras maps

Combinatorics 2025-06-19 v1 Representation Theory

Abstract

We study positive mm-divisible non-crossing partitions and their positive Kreweras maps. In classical types, we describe their combinatorial realisations as certain non-crossing set partitions. We also realise these positive Kreweras maps as pseudo-rotations on a circle, respectively on an annulus. We enumerate positive mm-divisible non-crossing partitions in classical types that are invariant under powers of the positive Kreweras maps with respect to several parameters. In order to cope with the exceptional types, we develop a different combinatorial model in general type describing positive mm-divisible non-crossing partitions that are invariant under powers of the positive Kreweras maps. We finally show that altogether these results establish several cyclic sieving phenomena.

Keywords

Cite

@article{arxiv.2506.14996,
  title  = {Positive $m$-divisible non-crossing partitions and their Kreweras maps},
  author = {Christian Krattenthaler and Christian Stump},
  journal= {arXiv preprint arXiv:2506.14996},
  year   = {2025}
}

Comments

AmS-LaTeX, 169 pages