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A359834
Parity of Dirichlet inverse of A359832, where A359832(n) = 1 if the 2-adic valuation of n is either 0 or odd, otherwise 0.
3
1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0
OFFSET
1
FORMULA
Multiplicative with a(2^e) = 1 if e is not a multiple of 3, otherwise 0, and for odd primes p, a(p^e) = 1 if e = 1, otherwise 0.
a(n) = A359833(n) mod 2.
Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 52/(7*Pi^2) = 0.752671... . - Amiram Eldar, Jan 25 2023
MATHEMATICA
f[p_, e_] := If[e == 1, 1, 0]; f[2, e_] := If[Divisible[e, 3], 0, 1]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Jan 25 2023 *)
PROG
(PARI) A359834(n) = { my(f = factor(n)); prod(k=1, #f~, if(2==f[k, 1], !!(f[k, 2]%3), (1==f[k, 2]))); };
CROSSREFS
Cf. also A359590.
Sequence in context: A351956 A092152 A350070 * A179775 A341952 A167686
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Jan 25 2023
STATUS
approved