@article{6acdfca0c758453596042ec461b55769,
title = "A problem of Ramanujan, Erds, and K{\'a}tai on the iterated divisor function",
abstract = "We determine asymptotically the maximal order of, where d(n) is the number of positive divisors of n. This solves a problem first put forth by Ramanujan in 1915.",
author = "Yvonne Buttkewitz and Christian Elsholtz and Kevin Ford and Schlage-Puchta, {Jan Christoph}",
note = "Funding Information: The work of Y. B. and C. E. was supported by the German Research Council (DFG-Grant-Number Funding Information: BU2488/1-3). K. F. was supported by National Science Foundation grant DMS-0901339.",
year = "2012",
month = sep,
doi = "10.1093/imrn/rnr175",
language = "English (US)",
volume = "2012",
pages = "4051--4061",
journal = "International Mathematics Research Notices",
issn = "1073-7928",
publisher = "Oxford University Press",
number = "17",
}