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%I #11 Jan 24 2020 20:58:45
%S 0,1,2,3,2,5,2,7,6,3,2,11,2,17,10,15,2,13,2,19,6,33,2,23,6,65,14,35,2,
%T 21,2,31,34,129,10,3,2,257,66,39,2,37,2,67,22,57,2,47,6,5,130,131,2,
%U 29,6,71,258,205,2,43,2,2049,38,21,34,69,2,259,514,41,2,55,2,4097,26,515,10,133,2,79,30,8193,2,15,66,16385,114,15,2,15,6,1027,410,10923
%N a(1) = 0; for n > 1, a(n) = A007947(A156552(n)).
%H Antti Karttunen, <a href="/A331602/b331602.txt">Table of n, a(n) for n = 1..10000</a> (based on Hans Havermann's factorization of A156552)
%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F a(1) = 0; and for n > 1, a(n) = A007947(A156552(n)).
%F A000035(a(n)) = 1 - A000035(n). [Flips the parity]
%t Array[Times @@ FactorInteger[#][[All, 1]] &@ Floor@ Total@ Flatten@ MapIndexed[#1 2^(#2 - 1) &, Flatten[Table[2^(PrimePi@ #1 - 1), {#2}] & @@@ FactorInteger@ #]] &, 94] (* _Michael De Vlieger_, Jan 24 2020 *)
%o (PARI)
%o A007947(n) = factorback(factorint(n)[, 1]);
%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 A331602(n) = A007947(A156552(n));
%Y Cf. A000035, A007947, A156552.
%Y Cf. also A322993.
%K nonn
%O 1,3
%A _Antti Karttunen_, Jan 22 2020
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