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A355837
Dirichlet inverse of A322327.
3
1, -2, -2, 0, -2, 4, -2, 2, 0, 4, -2, 0, -2, 4, 4, 0, -2, 0, -2, 0, 4, 4, -2, -4, 0, 4, 2, 0, -2, -8, -2, -2, 4, 4, 4, 0, -2, 4, 4, -4, -2, -8, -2, 0, 0, 4, -2, 0, 0, 0, 4, 0, -2, -4, 4, -4, 4, 4, -2, 0, -2, 4, 0, 0, 4, -8, -2, 0, 4, -8, -2, 0, -2, 4, 0, 0, 4, -8, -2, 0, 0, 4, -2, 0, 4, 4, 4, -4, -2, 0, 4, 0, 4, 4, 4, 4
OFFSET
1,2
FORMULA
Multiplicative with a(p^e) = 2 * (e mod 2) * (-1)^((e+1)/2) for prime p and e>0.
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A322327(n/d) * a(d).
Dirichlet g.f.: zeta(4*s)/(zeta(s)^2*zeta(2*s)). - Amiram Eldar, Dec 29 2022
MATHEMATICA
f[p_, e_] := 2 * (-1)^((e + 1)/2) * Mod[e, 2]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Jul 19 2022 *)
PROG
(PARI) A355837(n) = factorback(apply(e -> 2*(e%2)*((-1)^((1+e)/2)), factor(n)[, 2]));
CROSSREFS
Cf. A322327.
Sequence in context: A226177 A159916 A159286 * A372470 A261277 A006462
KEYWORD
sign,mult
AUTHOR
Antti Karttunen, Jul 19 2022, based on Werner Schulte's comment in A322327.
STATUS
approved