English

Formulas for the Generalized Frobenius Number of Triangular Numbers

Number Theory 2025-01-16 v1

Abstract

For k2 k \geq 2 , let A=(a1,a2,,ak) A = (a_{1}, a_{2}, \ldots, a_{k}) be a kk-tuple of positive integers with gcd(a1,a2,,ak)=1\gcd(a_{1}, a_2, \ldots, a_k) = 1. For a non-negative integer ss, the generalized Frobenius number of AA, denoted as g(A;s)=g(a1,a2,,ak;s)\mathtt{g}(A;s) = \mathtt{g}(a_1, a_2, \ldots, a_k;s), represents the largest integer that has at most ss representations in terms of a1,a2,,aka_1, a_2, \ldots, a_k with non-negative integer coefficients. In this article, we provide a formula for the generalized Frobenius number of three consecutive triangular numbers, g(tn,tn+1,tn+2;s)\mathtt{g}(t_{n}, t_{n+1}, t_{n+2};s) , valid for all s0s \geq 0 where tnt_n is given by (n+12)\binom{n+1}{2}. Furthermore, we present the proof of Komatsu's conjecture

Keywords

Cite

@article{arxiv.2501.08602,
  title  = {Formulas for the Generalized Frobenius Number of Triangular Numbers},
  author = {Kittipong Subwattanachai},
  journal= {arXiv preprint arXiv:2501.08602},
  year   = {2025}
}
R2 v1 2026-06-28T21:06:48.376Z