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%I #11 Nov 26 2017 07:14:55
%S 0,1,7,3,3,10,15,7,4,24,7,16,3,22,23,15,3,53,7,62,53,50,15,36,6,48,51,
%T 36,3,86,63,31,17,20,19,127,3,26,31,114,3,74,7,120,99,102,31,76,8,111,
%U 123,86,3,78,127,64,105,96,7,148,3,94,87,63,21,210,7,58,37,214,15,139,3,56
%N a(n) = n XOR sigma(n), where sigma(n) is the number of divisors of n, A000203.
%H Antti Karttunen, <a href="/A169813/b169813.txt">Table of n, a(n) for n = 1..16384</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>
%o (Scheme) (define (A169813 n) (A003987bi n (A000203 n))) ;; Where A003987bi implements the bitwise-XOR, A003987 and code for A000203 can be found under that entry. - _Antti Karttunen_, Nov 25 2017
%o (PARI) a(n) = bitxor(n, sigma(n)); \\ _Michel Marcus_, Nov 25 2017
%Y Cf. A000203, A003987, A070883, A169810, A169811, A169812, A169814.
%Y Cf. also A106409, A178910, A227320, A294899.
%K nonn,look
%O 1,3
%A _N. J. A. Sloane_, May 28 2010