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%I #10 Aug 11 2014 22:45:47
%S 3,3,3,3,3,3,3,3,5,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
%T 3,3,3,3,3,3,3,3,3,3,7,3,3,3,3,3,3,3,3,3,3,3,3,5,3,3,3,3,3,3,3,3,3,3,
%U 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3
%N Iterate k -> d(k) until an odd prime is reached, starting from the n-th composite.
%C a(n) is not 3 for n in {9, 45, 58, 89, 128, 163, 168, ...}.
%H Charles R Greathouse IV, <a href="/A200811/b200811.txt">Table of n, a(n) for n = 1..10000</a>
%H Tímea Csajbók and János Kasza, <a href="http://ac.inf.elte.hu/Vol_035_2011/083.pdf">Iterating the tau-function</a>, Annales Univ. Sci. Budapest., Sec. Math. 35 (2011), pp. 83-93.
%Y Cf. A200810, A200815.
%K nonn
%O 1,1
%A _Charles R Greathouse IV_, Nov 23 2011