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A318501
a(n) = SumXOR_{d|n} [moebius(n/d) > 0]*(sigma(d)-d).
3
0, 1, 1, 3, 1, 6, 1, 7, 4, 8, 1, 17, 1, 10, 9, 15, 1, 20, 1, 23, 11, 14, 1, 39, 6, 16, 13, 29, 1, 43, 1, 31, 15, 20, 13, 49, 1, 22, 17, 49, 1, 55, 1, 41, 32, 26, 1, 75, 8, 42, 21, 47, 1, 70, 17, 67, 23, 32, 1, 97, 1, 34, 40, 63, 19, 79, 1, 59, 27, 75, 1, 107, 1, 40, 48, 65, 19, 91, 1, 109, 40, 44, 1, 131, 23, 46, 33, 95, 1, 155, 21
OFFSET
1,4
LINKS
FORMULA
a(n) = A318502(n) XOR A318503(n).
PROG
(PARI) A318501(n) = { my(v=0); fordiv(n, d, if(1==moebius(n/d), v=bitxor(v, sigma(d)-d))); (v); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 28 2018
STATUS
approved