A169812 a(n) = n XOR d(n) (cf. A000005).

0, 0, 1, 7, 7, 2, 5, 12, 10, 14, 9, 10, 15, 10, 11, 21, 19, 20, 17, 18, 17, 18, 21, 16, 26, 30, 31, 26, 31, 22, 29, 38, 37, 38, 39, 45, 39, 34, 35, 32, 43, 34, 41, 42, 43, 42, 45, 58, 50, 52, 55, 50, 55, 62, 51, 48, 61, 62, 57, 48, 63, 58, 57, 71, 69, 74, 65, 66, 65, 78, 69, 68, 75, 78

Offset: 1

Author

N. J. A. Sloane, May 28 2010

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000005, A070883, A169810, A169811, A169813, A169814.

Programs

Mathematica

a[n_] := BitXor[n, DivisorSigma[0, n]]; Array[a, 100] (* Amiram Eldar, Jul 08 2019 *)

PARI

a(n)=bitxor(n, numdiv(n)); \\ Michel Marcus, Jul 08 2019