arXiv 1108.18152011-08-08math.NT

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

Yvonne Buttkewitz, Christian Elsholtz, Kevin Ford, Jan-Christoph Schlage-Puchta

备注：: 8 pages
发表信息：: Internat. Math. Res. Notices 2012 (2012), 4051-4061

英文摘要：

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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