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arXiv · 0802.1106

Extremal orders of compositions of certain arithmetical functions

József Sándor·László Tóth
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Abstract

We study the exact extremal orders of compositions $f(g(n))$ of certain arithmetical functions, including the functions $σ(n)$, $ϕ(n)$, $σ^*(n)$ and $ϕ^*(n)$, representing the sum of divisors of $n$, Euler's function and their unitary analogues, respectively. Our results complete, generalize and refine known results.

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József Sándor, László Tóth. 2008-09-01. Extremal orders of compositions of certain arithmetical functions. https://arxiv.org/abs/0802.1106

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