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%I #7 Apr 14 2019 17:23:07
%S 1,1,2,3,4,2,8,7,6,4,16,6,32,8,8,15,64,6,128,12,16,16,256,14,12,32,14,
%T 24,512,8,1024,31,32,64,32,18,2048,128,64,28,4096,16,8192,48,24,256,
%U 16384,30,24,12,128,96,32768,14,64,56,256,512,65536,24,131072,1024,48,63,128,32,262144,192,512,32,524288,42,1048576,2048,24,384
%N Multiplicative with a(p^e) = A156552(p^e).
%H Antti Karttunen, <a href="/A324911/b324911.txt">Table of n, a(n) for n = 1..4096</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>
%e For n = 900 = 2^2 * 3^2 * 5^2, a(900) = A156552(4) * A156552(9) * A156552(25) = 3*6*12 = 216.
%o (PARI)
%o A156552(n) = { my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res }; \\ From A156552
%o A324911(n) = { my(f=factor(n)); prod(i=1, #f~, A156552(f[i,1]^f[i,2])); };
%Y Cf. A156552, A324910, A324912.
%Y Cf. also A324106.
%K nonn,mult
%O 1,3
%A _Antti Karttunen_, Apr 14 2019
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