A318460 a(n) = Sum_{d|n, d < n/d} (d XOR n/d), where XOR is bitwise-xor (A003987).

0, 3, 2, 5, 4, 8, 6, 15, 8, 18, 10, 24, 12, 20, 20, 27, 16, 35, 18, 30, 24, 32, 22, 52, 24, 42, 36, 44, 28, 56, 30, 63, 40, 54, 36, 81, 36, 56, 52, 90, 40, 80, 42, 80, 68, 68, 46, 116, 48, 93, 68, 86, 52, 112, 68, 112, 72, 90, 58, 144, 60, 92, 98, 119, 72, 136, 66, 122, 88, 128, 70, 171, 72, 114, 110, 136, 88, 152, 78

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..16384

Index entries for sequences related to binary expansion of n

Index entries for sequences related to sigma(n)

Formula

a(n) = (1/2) * Sum_{d|n} (d XOR n/d).

a(n) = A318462(n) - A037213(n).

Prog

(PARI) A318460(n) = { my(xors=0); fordiv(n, d, if(d<(n/d), xors += bitxor(d, n/d))); (xors); };

Crossrefs

Cf. A003987, A037213, A318461, A318462, A318463.

Sequence in context: A169752 A095720 A348542 * A276582 A240729 A339371

Adjacent sequences: A318457 A318458 A318459 * A318461 A318462 A318463

Keyword

nonn,base

Author

Antti Karttunen, Aug 28 2018

Status

approved