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a(n) = 1 if n is a product of a prime and the square of a different prime (p^2 * q), otherwise 0.
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%I #11 Apr 22 2022 06:03:34

%S 0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,

%T 0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1,

%U 0,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0

%N a(n) = 1 if n is a product of a prime and the square of a different prime (p^2 * q), otherwise 0.

%H Antti Karttunen, <a href="/A353472/b353472.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>

%H <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>

%F a(n) = A353473(n) + A353474(n).

%F a(n) = [A000005(n) == 3+A001222(n)], where [ ] is the Iverson bracket.

%o (PARI) A353472(n) = (numdiv(n) == (3+bigomega(n)));

%Y Characteristic function of A054753.

%Y Cf. A000005, A001222, A353473, A353474.

%K nonn

%O 1

%A _Antti Karttunen_, Apr 21 2022