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%I A324398 #7 Mar 05 2019 18:19:52
%S A324398 0,0,0,1,0,1,0,1,6,0,0,1,0,1,8,9,0,1,0,1,16,1,0,1,0,1,10,1,0,1,0,1,0,
%T A324398 1,20,9,0,1,66,1,0,1,0,1,6,1,0,1,0,0,2,1,0,1,36,1,258,1,0,1,0,1,6,41,
%U A324398 0,1,0,1,0,1,0,17,0,1,16,1,32,1,0,1,10,1,0,1,132,1,1026,1,0,33,72,1,0,1,256,25,0,0,66,17,0,1,0,1,34
%N A324398 a(1) = 0; for n > 1, a(n) = A318458(A156552(n)).
%H A324398 Antti Karttunen, <a href="/A324398/b324398.txt">Table of n, a(n) for n = 1..4473</a>
%H A324398 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A324398 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%H A324398 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A324398 a(1) = 0; for n > 1, a(n) = A318458(A156552(n)).
%F A324398 a(n) = A156552(n) AND (A323243(n) - A156552(n)).
%o A324398 (PARI)
%o A324398 A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A324398 A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
%o A324398 A318458(n) = bitand(n, sigma(n)-n);
%o A324398 A324398(n) = if(1==n,0,A318458(A156552(n)));
%Y A324398 Cf. A000203, A156552, A318458, A323243, A323244, A324396, A324397.
%K A324398 nonn
%O A324398 1,9
%A A324398 _Antti Karttunen_, Mar 05 2019

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