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A353380
a(n) = 1 if A353354(n) [= Sum_{d|n} A332823(d)] is zero, otherwise 0.
8
1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 1, 1
OFFSET
1
FORMULA
a(n) = [A353328(n) = A353329(n)], where [ ] is the Iverson bracket, giving 1 only if A353328(n) and A353329(n) are equal, and 0 otherwise.
a(p) = 0 for all primes p.
a(n) = a(A003961(n)) = a(A348717(n)), for all n >= 1.
PROG
(PARI)
A332823(n) = { my(f = factor(n), u=(sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2)%3); if(2==u, -1, u); };
A353354(n) = sumdiv(n, d, A332823(d));
A353380(n) = (0==A353354(n));
CROSSREFS
Characteristic function of A353355.
Cf. A048675, A332823, A353328, A353329, A353354, A353381, A353382 (inverse Möbius transform), A353414.
Sequence in context: A266672 A266070 A262855 * A204171 A267612 A242252
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 16 2022
STATUS
approved