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arXiv · 2404.08190

End behavior of Ramanujan's taxicab numbers

Brennan Benfield·Oliver Lippard·Arindam Roy
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Abstract

Generalized taxicab numbers are the smallest positive integers that are the sum of exactly $j$, positive $k$-th powers in exactly $m$ distinct ways. This paper is considers for which values of $m$ does a smallest such integer exist as $j$ gets large. There appear to be only two possible outcomes, leading to curious results like there is no positive integer that can be expressed as the sum of exactly $10$ positive squares in exactly $3$ ways. This paper resolves a number of conjectures found in the OEIS by considering generalized Taxicab numbers in the setting of the theory of partitions.

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Brennan Benfield, Oliver Lippard, Arindam Roy. 2024-04-12. End behavior of Ramanujan's taxicab numbers. https://arxiv.org/abs/2404.08190

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