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A378528
Dirichlet inverse of A378444.
2
1, -1, -1, 0, -1, 1, -1, 0, -1, 1, -1, -1, -1, 1, 0, -1, -1, 1, -1, -1, 0, 1, -1, 1, -1, 1, 1, -1, -1, 0, -1, 1, 0, 1, 0, 1, -1, 1, 0, 1, -1, 0, -1, -1, 2, 1, -1, 1, -1, 1, 0, -1, -1, -1, 0, 1, 0, 1, -1, 2, -1, 1, 2, 0, 0, 0, -1, -1, 0, 0, -1, -1, -1, 1, 2, -1, 0, 0, -1, 1, 0, 1, -1, 2, 0, 1, 0, 1, -1, -2, 0, -1, 0, 1, 0, -1, -1, 1, 2, 1, -1, 0, -1, 1, 2
OFFSET
1,45
LINKS
FORMULA
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A378444(n/d) * a(d).
a(n) = Sum_{d|n} A000010(n/d)*A378527(d).
a(n) = Sum_{d|n} A008683(n/d)*A369974(d).
PROG
(PARI)
A083345(n) = { my(f=factor(n)); numerator(vecsum(vector(#f~, i, f[i, 2]/f[i, 1]))); };
A369001(n) = !(A083345(n)%2);
A378444(n) = sumdiv(n, d, A369001(d));
memoA378528 = Map();
A378528(n) = if(1==n, 1, my(v); if(mapisdefined(memoA378528, n, &v), v, v = -sumdiv(n, d, if(d<n, A378444(n/d)*A378528(d), 0)); mapput(memoA378528, n, v); (v)));
CROSSREFS
Möbius transform of A369974.
Sequence in context: A181506 A319797 A169987 * A267611 A178666 A206706
KEYWORD
sign
AUTHOR
Antti Karttunen, Dec 01 2024
STATUS
approved