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A318456 a(n) = n OR A001065(n), where OR is bitwise-or (A003986) and A001065 = sum of proper divisors.

%I A318456 #16 Mar 11 2024 08:50:25
%S A318456 1,3,3,7,5,6,7,15,13,10,11,28,13,14,15,31,17,23,19,22,31,30,23,60,31,
%T A318456 26,31,28,29,62,31,63,47,54,47,55,37,54,55,58,41,62,43,44,45,62,47,
%U A318456 124,57,59,55,62,53,118,55,120,63,58,59,124,61,62,63,127,83,78,67,126,95,78,71,123,73,106,123,76,95,94,79,122,121,126,83
%N A318456 a(n) = n OR A001065(n), where OR is bitwise-or (A003986) and A001065 = sum of proper divisors.
%H A318456 Antti Karttunen, <a href="/A318456/b318456.txt">Table of n, a(n) for n = 1..65537</a>
%H A318456 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A318456 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A318456 a(n) = A003986(n, A001065(n)).
%F A318456 a(n) = A000203(n) - A318458(n).
%t A318456 Array[BitOr[#, DivisorSigma[1, #] - #] &, 100] (* _Paolo Xausa_, Mar 11 2024 *)
%o A318456 (PARI) A318456(n) = bitor(n,sigma(n)-n);
%o A318456 (Python)
%o A318456 from sympy import divisor_sigma
%o A318456 def A318456(n): return n|divisor_sigma(n)-n # _Chai Wah Wu_, Jul 01 2022
%Y A318456 Cf. A000203, A001065, A003986, A318457, A318458, A318466.
%K A318456 nonn,base
%O A318456 1,2
%A A318456 _Antti Karttunen_, Aug 26 2018