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A353468
Dirichlet inverse of A353467.
4
1, 1, -1, -1, 1, 1, -1, 2, 2, -1, 1, -3, -1, 1, -3, -5, 1, -1, -1, 3, 3, -1, 1, 10, -1, 1, -5, -3, -1, 1, 1, 14, -3, -1, 1, 0, -1, 1, 3, -10, 1, -1, -1, 3, 10, -1, 1, -35, 2, 2, -3, -3, -1, 2, -1, 10, 3, 1, 1, 3, -1, -1, -10, -42, 1, 1, 1, 3, -3, -3, -1, 10, 1, 1, 0, -3, -3, -1, -1, 35, 14, -1, 1, -3, -1, 1, 3, -10
OFFSET
1,8
FORMULA
a(1) = 1, for n > 1, a(n) = -Sum_{d|n, d<n} A353467(n/d) * a(d).
a(n) = A353467(A252463(n)).
For all n >= 1, a(A000040(n)) = ((-1)^(n-1)).
PROG
(PARI)
A252463(n) = if(!(n%2), n/2, my(f=factor(n)); for(i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f));
memoA353467 = Map();
A353467(n) = if(1==n, 1, my(v); if(mapisdefined(memoA353467, n, &v), v, v = -sumdiv(n, d, if(d<n, A353467(A252463(n/d))*A353467(d), 0)); mapput(memoA353467, n, v); (v)));
CROSSREFS
Cf. A000040, A252463, A353467 [Dirichlet inverse], A353469 [sum with it].
Cf. also A353458.
Sequence in context: A318810 A319989 A338117 * A184305 A337279 A157522
KEYWORD
sign
AUTHOR
Antti Karttunen, Apr 21 2022
STATUS
approved