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TIGHT UNIVERSAL TRIANGULAR FORMS

Published online by Cambridge University Press:  18 November 2021

MINGYU KIM*
Affiliation:
Department of Mathematics, Sungkyunkwan University, Suwon 16419, Korea

Abstract

For a subset S of nonnegative integers and a vector $\mathbf {a}=(a_1,\ldots ,a_k)$ of positive integers, define the set $V^{\prime }_S(\mathbf {a})=\{ a_1s_1+\cdots +a_ks_k : s_i\in S\}-\{0\}$ . For a positive integer n, let $\mathcal T(n)$ be the set of integers greater than or equal to n. We consider the problem of finding all vectors $\mathbf {a}$ satisfying $V^{\prime }_S(\mathbf {a})=\mathcal T(n)$ when S is the set of (generalised) m-gonal numbers and n is a positive integer. In particular, we completely resolve the case when S is the set of triangular numbers.

Type
Research Article
Copyright
© The Author(s), 2021. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.

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Footnotes

This work was supported by a National Research Foundation of Korea (NRF) grant funded by the government of Korea (MSIT) (NRF-2021R1C1C2010133).

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