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arXiv · 2604.07826

Universal sums of generalized polygonal numbers of almost prime length

Soumyarup Banerjee·Ben Kane·Kwan To Ng
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Abstract

In this paper, we consider universal sums of generalized polygonal numbers. Fixing $m\in\mathbb{N}_{\geq 3}$, we show two finiteness theorems for universal sums of generalized polygonal numbers whose inputs have a restricted number $L$ of prime divisors (counting multiplicity) away from an finite set of exceptional primes. In the first theorem, we fix $m$ and uniformly bound the finite check independent of $L\geq 900$, and in the second theorem, we give an optimal bound for the finiteness check if $L$ is larger than a constant times $\log(m)$.

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Soumyarup Banerjee, Ben Kane, Kwan To Ng. 2026-04-09. Universal sums of generalized polygonal numbers of almost prime length. https://arxiv.org/abs/2604.07826

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