English

Multimodal sequences and their generating functions

Number Theory 2025-06-25 v3 Combinatorics

Abstract

We define integer multimodal sequences, which are generalizations of unimodal sequences having multiple local peaks of equal size. The generating functions for multimodal sequences represent novel types of qq-series that combine generating functions for both integer partitions and integer compositions. We prove a bijection between multimodal sequences of equal size (sum), and show that multimodal generating functions become finite series at roots of unity like the ``strange'' function of Kontsevich, quantum modular forms, and other examples of this phenomenon in the qq-series literature.

Keywords

Cite

@article{arxiv.2310.02796,
  title  = {Multimodal sequences and their generating functions},
  author = {Philip Cuthbertson and Robert Schneider},
  journal= {arXiv preprint arXiv:2310.02796},
  year   = {2025}
}

Comments

13 pages, submitted for publication

R2 v1 2026-06-28T12:40:24.520Z