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%I #21 Sep 08 2022 08:45:23
%S 4,10,22,34,46,58,82,94,106,118,142,166,178,202,214,226,262,274,298,
%T 334,346,358,382,394,454,466,478,502,514,526,538,562,586,622,634,694,
%U 706,718,766,778,802,838,862,886,898,922,934,958,982,1006,1018,1042,1114
%N Semiprimes of the form 6n+4.
%C {6} + A112772 + A112774 = A100484 = 2*A000040.
%H Vincenzo Librandi, <a href="/A112774/b112774.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = 2 * A003627(n) = 6 * A024893(n) + 4.
%t Select[6 Range[0, 200] + 4, PrimeOmega[#] == 2&] (* _Vincenzo Librandi_, Sep 22 2012 *)
%o (Magma) IsSemiprime:=func<n | &+[d[2]: d in Factorization(n)] eq 2>; [s: n in [0..200] | IsSemiprime(s) where s is 6*n + 4]; // _Vincenzo Librandi_, Sep 22 2012
%o (Python)
%o from sympy import factorint
%o def semiprime(n): f = factorint(n); return sum(f[p] for p in f) == 2
%o print(list(filter(semiprime, range(4, 1115, 6)))) # _Michael S. Branicky_, Apr 10 2021
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_ and _Ray Chandler_, Oct 15 2005
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