A318462 - OEIS

A318462

a(n) = Sum_{d|n, d < n/d} (d XOR n/d) + {square root of n when n is a square}.

1, 3, 2, 7, 4, 8, 6, 15, 11, 18, 10, 24, 12, 20, 20, 31, 16, 35, 18, 30, 24, 32, 22, 52, 29, 42, 36, 44, 28, 56, 30, 63, 40, 54, 36, 87, 36, 56, 52, 90, 40, 80, 42, 80, 68, 68, 46, 116, 55, 93, 68, 86, 52, 112, 68, 112, 72, 90, 58, 144, 60, 92, 98, 127, 72, 136, 66, 122, 88, 128, 70, 171, 72, 114, 110, 136, 88, 152, 78

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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) = A318460(n) + A037213(n) = A000203(n) - 2*A318463(n).

PROG

(PARI) A318462(n) = { my(xors=0); fordiv(n, d, if(d<(n/d), xors += bitxor(d, n/d), if(d==(n/d), xors += d))); (xors); };

CROSSREFS