Multiplicative structures of values of the sum-of-divisors function

Tomohiro Yamada

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Multiplicative structures of values of the sum-of-divisors function

Tomohiro Yamada

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Abstract

We study equations of the form $σ(p^{q-1})=Az$, where $p$ is a prime, $q$ is a fixed odd prime, $A$ is a fixed integer and $z$ is an integer composed of primes in a fixed finite set. We shall improve upper bounds for the size and the number of solutions of such equations.

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Tomohiro Yamada. 2005-12-08. Multiplicative structures of values of the sum-of-divisors function. https://arxiv.org/abs/math/0512175

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