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%I #13 Aug 08 2017 22:14:56
%S 0,1,1,2,1,3,1,3,2,4,1,5,1,5,2,5,1,6,1,6,3,6,1,7,2,4,3,7,1,4,1,7,2,6,
%T 2,8,1,6,4,8,1,9,1,8,4,8,1,10,2,9,2,6,1,11,4,10,4,9,1,6,1,10,5,10,2,4,
%U 1,11,3,4,1,12,1,4,4,8,2,8,1,12,5,9,1,13,4,6,2,12,1,9,2,12,4,12,2,14,1,8,4,13,1,9,1,8,4
%N Filter-sequence for the prime signature of cototient: a(1) = 0; for n > 1, a(n) = A101296(A051953(n)).
%H Antti Karttunen, <a href="/A290089/b290089.txt">Table of n, a(n) for n = 1..16384</a>
%F a(1) = 0; for n > 1, a(n) = A101296(A051953(n)).
%Y Cf. A051953, A101296, A277906, A290087.
%Y Cf. A000040 (the positions of 1's), A050530 (the positions of 2's).
%K nonn
%O 1,4
%A _Antti Karttunen_, Aug 07 2017