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A353418
Dirichlet inverse of A353269.
8
1, 0, 0, -1, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0, 0, -1, 0, 0, 0, 0, -1, 0, 0, 0, -1, 0, 1, 0, 0, -1, 1, 0, 0, 0, 0, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, -1, 0, -1, 0, 0, 0, 0, -1, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 1, -1, 0, -1, 1, 0, 1, -1, 0, 0, -1, 0, 0, 0, 0, 0, 2
OFFSET
1,100
FORMULA
a(1) = 1; a(n) = -Sum_{d|n, d < n} A353269(n/d) * a(d).
a(n) = A353419(n) - A353269(n).
a(p) = 0 for all primes p.
a(n) = a(A003961(n)) = a(A348717(n)), for all n >= 1.
PROG
(PARI)
up_to = 65537;
DirInverseCorrect(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = (-u[1]*sumdiv(n, d, if(d<n, v[n/d]*u[d], 0)))); (u) }; \\ Compute the Dirichlet inverse of the sequence given in input vector v
A156552(n) = { my(f = factor(n), p, p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res };
A353269(n) = (!(A156552(n)%3));
v353418 = DirInverseCorrect(vector(up_to, n, A353269(n)));
A353418(n) = v353418[n];
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Apr 19 2022
STATUS
approved