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%I #26 Feb 27 2022 22:22:35
%S 1,2,2,3,4,4,3,4,6,5,6,6,8,8,6,9,8,10,12,7,12,10,12,12,12,9,12,16,8,
%T 15,12,16,18,14,12,16,12,20,9,18,14,20,24,16,15,20,14,24,24,10,21,24,
%U 16,24,30,18,18,24,16,28,30,11,24,30,18,28,36,20,21,40,28,18,32,36,12,27,36,32,42,22,48,32,20,45,36,42,13,48,30,42,60,36,48
%N Number of divisors of A002183(n).
%C No prime number > 17 is in this sequence. - _J. Lowell_, Feb 06 2022
%D S. Ramanujan, Collected Papers, Ed. G. H. Hardy et al., Cambridge 1927; Chelsea, NY, 1962, p. 87.
%H Charles R Greathouse IV, <a href="/A243220/b243220.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000005(A000005(A002182(n))). - _Michel Marcus_, Oct 08 2016
%t (* This program is not suitable to compute a large number of terms. *) Reap[For[record = 0; n = 1, n <= 10^9, n = If[n < 60, n + 1, n + 60], tau = DivisorSigma[0, n]; If[tau > record, record = tau; t = DivisorSigma[0, tau]; Print[t]; Sow[t]]]][[2, 1]] (* _Jean-François Alcover_, Oct 08 2016 *)
%Y Cf. A000005, A002183, A002182.
%K nonn,look
%O 1,2
%A _N. J. A. Sloane_, Jun 01 2014
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