Editing Iterated logarithm (section)

==Other applications==
The iterated logarithm is closely related to the [[generalized logarithm function]] used in [[symmetric level-index arithmetic]]. The additive [[persistence of a number]], the number of times someone must replace the number by the sum of its digits before reaching its [[digital root]], is <math>O(\log^* n)</math>.

In [[computational complexity theory]], Santhanam<ref>{{cite conference
 | last = Santhanam | first = Rahul
 | contribution = On separators, segregators and time versus space
 | contribution-url = https://scholar.archive.org/work/jsi2cizbpbcsrkq3annbprthsm/access/wayback/http://homepages.inf.ed.ac.uk/rsanthan/Papers/segsepfinal.pdf
 | doi = 10.1109/CCC.2001.933895
 | pages = 286–294
 | publisher = [[IEEE Computer Society]]
 | title = Proceedings of the 16th Annual IEEE Conference on Computational Complexity, Chicago, Illinois, USA, June 18-21, 2001
 | title-link = Computational Complexity Conference
 | year = 2001| isbn = 0-7695-1053-1
 }}</ref> shows that the [[computational resource]]s [[DTIME]] — [[time complexity|computation time]] for a [[Turing machine|deterministic Turing machine]] — and [[NTIME]] — computation time for a [[non-deterministic Turing machine]] — are distinct up to <math>n\sqrt{\log^*n}.</math>