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%I #9 Mar 27 2019 18:56:41
%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
%N a(n) = A324863(n) - A252464(n).
%C Question: Are there any other terms than 0's and 1's ? There are only 201 nonzero values among the first 10000 terms and they are all 1's.
%C A324871 gives the numbers n where a(n) <> 0. The first such number which is not a square is 187 = 11*17.
%H Antti Karttunen, <a href="/A324870/b324870.txt">Table of n, a(n) for n = 1..10000</a> (based on Hans Havermann's factorization of A156552)
%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(n) = A324863(n) - A252464(n).
%o (PARI)
%o A061395(n) = if(1==n, 0, primepi(vecmax(factor(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 A252464(n) = if(1==n, 0, (bigomega(n) + A061395(n) - 1));
%o A324866(n) = { my(k=A156552(n)); bitor(k,(A323243(n)-k)); }; \\ Needs also code from A323243.
%o A324863(n) = #binary(A324866(n));
%o A324870(n) = (A324863(n) - A252464(n));
%Y Cf. A156552, A252464, A324863, A324866, A324871, A324872.
%K nonn
%O 1
%A _Antti Karttunen_, Mar 21 2019
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