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%I #8 Jul 31 2020 16:42:47
%S 1,1,1,1,1,1,1,1,2,1,1,1,2,1,1,1,1,2,2,1,2,1,1,1,1,1,1,2,1,1,2,1,1,2,
%T 1,2,2,1,2,2,1,1,2,2,1,1,1,1,2,2,1,2,2,1,1,1,1,2,1,1,2,1,3,1,2,2,2,1,
%U 1,2,1,2,2,2,1,2,1,1,1,2,2,1,2,2,1,2,1,1,2,2,1,1,2,2,1,2,2,2,1,2,1,2,3,1,1
%N Number of distinct prime factors of 1+sigma(n).
%H Antti Karttunen, <a href="/A336691/b336691.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F a(n) = A001221(1+A000203(n)) = A001221(A088580(n)).
%o (PARI) A336691(n) = omega(1+sigma(n));
%Y Cf. A000203, A001221, A088580, A058062, A332459, A336692, A336693, A336694, A336695.
%K nonn
%O 1,9
%A _Antti Karttunen_, Jul 31 2020
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