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A378597
Möbius transform of A378450, where A378450 is the number of positive numbers k <= sigma(n) that are not a sum of any subset of distinct divisors of n.
2
0, 0, 1, 0, 3, -1, 5, 0, 5, 0, 9, 0, 11, 4, 5, 0, 15, -5, 17, -3, 11, 12, 21, 0, 21, 16, 19, -9, 27, -8, 29, 0, 23, 24, 25, 0, 35, 28, 29, 0, 39, -20, 41, 0, 9, 36, 45, 0, 45, 6, 41, 8, 51, -19, 45, 0, 47, 48, 57, 3, 59, 52, 23, 0, 55, -44, 65, 24, 59, -35, 69, 0, 71, 64, 31, 32, 67, -56, 77, 0, 65, 72, 81, 9, 75, 76, 77, -21
OFFSET
1,5
LINKS
FORMULA
a(n) = Sum_{d|n} A008683(d)*A378450(n/d).
a(n) = n - A378596(n).
PROG
(PARI)
A119347(n) = { my(c=[0]); fordiv(n, d, c = Set(concat(c, vector(#c, i, c[i]+d)))); (#c)-1; };
A378450(n) = (sigma(n)-A119347(n));
A378597(n) = sumdiv(n, d, moebius(n/d)*A378450(d));
CROSSREFS
KEYWORD
sign,look
AUTHOR
Antti Karttunen, Dec 02 2024
STATUS
approved