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%I #9 Apr 22 2022 10:40:48
%S 0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1,1,
%T 0,0,0,1,1,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,1,0,0,0,1,0,0,0,0,0,0,
%U 1,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,1,0,0,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0
%N a(n) = 1 if n is a semiprime of the form p * q, where p and q are primes with p^2 < q, otherwise 0.
%H Antti Karttunen, <a href="/A353475/b353475.txt">Table of n, a(n) for n = 1..65537</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(n) = A064911(n) - A353476(n).
%o (PARI) A353475(n) = { my(f=factor(n)); if(#f~ != 2, 0, (1==f[1,2] && 1==f[2,2] && (f[1,1]^2) < f[2,1])); };
%Y Characteristic function of A138511, semiprimes where the larger prime factor is greater than the square of the smaller prime factor.
%Y Cf. A064911, A353476.
%K nonn
%O 1
%A _Antti Karttunen_, Apr 22 2022
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