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arXiv · 1108.1815

A problem of Ramanujan, Erdos and Katai on the iterated divisor function

Yvonne Buttkewitz·Christian Elsholtz·Kevin Ford·Jan-Christoph Schlage-Puchta
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Abstract

We determine asymptotically the maximal order of log d(d(n)), where d(n) is the number of positive divisors of n. This solves a problem first put forth by Ramanujan in 1915.

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Yvonne Buttkewitz, Christian Elsholtz, Kevin Ford, Jan-Christoph Schlage-Puchta. 2011-08-08. A problem of Ramanujan, Erdos and Katai on the iterated divisor function. https://arxiv.org/abs/1108.1815

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