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A324658 a(n) = n - A324659(n), where A324659(n) is half of bitwise-AND of 2*n and sigma(n).

%I A324658 #12 Mar 13 2024 04:43:07
%S A324658 1,2,1,4,4,0,3,8,9,2,9,0,8,2,3,16,16,0,17,0,5,4,19,0,16,10,11,0,16,26,
%T A324658 15,32,33,32,35,0,36,32,35,0,40,10,41,4,8,10,39,0,33,16,19,4,36,2,19,
%U A324658 0,17,18,33,40,32,14,11,64,65,2,65,64,69,6,67,8,72,66,65,8,77,10,71,0,65,64,81,4,65,20,67,0,80
%N A324658 a(n) = n - A324659(n), where A324659(n) is half of bitwise-AND of 2*n and sigma(n).
%H A324658 Antti Karttunen, <a href="/A324658/b324658.txt">Table of n, a(n) for n = 1..16384</a>
%H A324658 Antti Karttunen, <a href="/A324658/a324658.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%H A324658 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A324658 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A324658 a(n) = n - A324659(n) = n - A318468(n)/2 = n - ((2*n AND sigma(n))/2).
%t A324658 Array[# - BitAnd[2*#, DivisorSigma[1, #]]/2 &, 100] (* _Paolo Xausa_, Mar 13 2024 *)
%o A324658 (PARI) A324658(n) = (n-(bitand(2*n,sigma(n))/2));
%Y A324658 Cf. A000203, A004198, A318468, A324648, A324659.
%Y A324658 Cf. A324652 (positions of zeros).
%K A324658 nonn,look
%O A324658 1,2
%A A324658 _Antti Karttunen_, Mar 14 2019