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%I #15 Jul 27 2023 04:59:27
%S 1,0,0,1,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0,
%T 0,0,0,1,0,0,1,0,1,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 1,0,0,1,1,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0
%N a(n) = 1 if the 2-adic and 3-adic valuations of A025487(n) are equal, 0 otherwise.
%H Antti Karttunen, <a href="/A330682/b330682.txt">Table of n, a(n) for n = 1..47617</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>.
%F a(n) = [A007814(A025487(n)) == A007949(A025487(n))], where [ ] is the Iverson bracket.
%F a(n) = A000035(A181815(n)) = A181815(n) mod 2.
%F a(A329897(n)) = 1, a(A329898(n)) = 0.
%t s = {1}; Do[If[GreaterEqual @@ (f = FactorInteger[n])[[;; , 2]] && PrimePi[f[[-1, 1]]] == Length[f], AppendTo[s, If[Equal @@ IntegerExponent[n, {2, 3}], 1, 0]]], {n, 2, 50000}]; s (* _Amiram Eldar_, Jul 27 2023 *)
%o (PARI) A330682(n) = (A181815(n)%2);
%Y Characteristic function of A329897.
%Y Cf. A007814, A007949, A025487, A181815, A329898.
%K nonn
%O 1
%A _Antti Karttunen_, Dec 24 2019
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