English

On consecutive sums in permutations

Combinatorics 2021-08-31 v5 Number Theory

Abstract

We study the number of values taken by the sums i=uv1ai\sum_{i=u}^{v-1} a_i, where a1,a2,,ana_1,a_2,\dots,a_n is a permutation of 1,2,,n1,2,\dots,n and 1u<vn+11 \leq u < v \leq n+1. In particular, we show that for a random choice of a permutation, with high probability there are (1+e24+o(1))n2(\frac{1+e^{-2}}{4} +o(1)) n^2 such sums. This answers an old question of Erd\H{o}s and Harzheim. We also obtain non-trivial bounds on the maximum possible number of distinct sums, ranging over all permutations of 1,2,,n1,2,\dots,n. We close with some questions concerning the minimal possible number of distinct sums.

Keywords

Cite

@article{arxiv.1504.07156,
  title  = {On consecutive sums in permutations},
  author = {Jakub Konieczny},
  journal= {arXiv preprint arXiv:1504.07156},
  year   = {2021}
}

Comments

46 pages

R2 v1 2026-06-22T09:23:32.112Z