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a(n) = n XOR A001065(n), where XOR is bitwise-xor (A003987) and A001065 = sum of proper divisors.
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%I #8 Aug 26 2018 20:14:08

%S 1,3,2,7,4,0,6,15,13,2,10,28,12,4,6,31,16,7,18,2,30,24,22,60,31,10,22,

%T 0,28,52,30,63,46,54,46,19,36,48,54,26,40,28,42,4,12,52,46,124,57,25,

%U 38,26,52,116,38,120,46,26,58,80,60,28,22,127,82,12,66,126,94,12,70,51,72,98,122,12,94,20,78,58,121,126,82,216,66

%N a(n) = n XOR A001065(n), where XOR is bitwise-xor (A003987) and A001065 = sum of proper divisors.

%H Antti Karttunen, <a href="/A318457/b318457.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = A003987(n, A001065(n)).

%F a(n) = A000203(n) - 2*A318458(n).

%o (PARI) A318457(n) = bitxor(n,sigma(n)-n);

%Y Cf. A000203, A001065, A003987, A033879, A318456, A318458, A318467.

%Y Cf. A000396 (positions of zeros).

%K nonn,base

%O 1,2

%A _Antti Karttunen_, Aug 26 2018