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a(1) = 0; for n > 1, a(n) = A033879(A048675(n)).
7

%I #8 Mar 08 2019 20:15:20

%S 0,1,1,1,1,2,1,2,1,4,1,1,1,5,0,1,1,4,1,0,2,16,1,4,1,18,0,2,1,6,1,4,-3,

%T 46,-4,0,1,82,14,6,1,10,1,-3,1,256,1,0,1,5,-12,14,1,6,-2,10,8,226,1,1,

%U 1,748,-4,0,-19,18,1,-12,-12,12,1,6,1,1362,2,8,-12,22,1,1,1,3838,1,-4,10,5458,254,18,1,5,-10,-12,-348,12250

%N a(1) = 0; for n > 1, a(n) = A033879(A048675(n)).

%H Antti Karttunen, <a href="/A324575/b324575.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(1) = 0; for n > 1, a(n) = A033879(A048675(n)).

%F a(n) = 2*A048675(n) - A324573(n).

%F a(A007947(n)) = A324574(n).

%F a(p) = 1 for all primes p.

%o (PARI)

%o A033879(n) = (2*n-sigma(n));

%o A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; };

%o A324575(n) = if(1==n,0,A033879(A048675(n)));

%Y Cf. A007947, A033879, A048675, A324573, A324574.

%Y Cf. also A323244, A323174, A324546.

%K sign

%O 1,6

%A _Antti Karttunen_, Mar 07 2019