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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A360741 Semiprimes of the form k^2 + 4.

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%I A360741 #22 Mar 13 2023 16:22:25
%S A360741 4,85,365,445,533,629,965,1685,1853,2605,2813,3029,3973,4765,5045,
%T A360741 5629,5933,6245,6893,8285,8653,11029,11453,11885,12773,14165,15133,
%U A360741 16645,17165,17693,20453,21029,22205,22805,23413,24653,27229,29245,29933,30629,32765,34229
%N A360741 Semiprimes of the form k^2 + 4.
%C A360741 A242332 gives the corresponding values of k.
%C A360741 Except for 4, all terms == 5 (mod 8). - _Robert Israel_, Feb 18 2023
%F A360741 a(n) = A242332(n)^2 + 4.
%e A360741 85 is a term because 9^2 + 4 = 85 = 5*17.
%p A360741 select(t -> numtheory:-bigomega(t)=2, [seq(i^2+4,i=0..1000)]); # _Robert Israel_, Feb 18 2023
%t A360741 Select[Range[0, 200]^2 + 4, PrimeOmega[#] == 2 &] (* _Amiram Eldar_, Feb 18 2023 *)
%Y A360741 Cf. A001358, A085722, A087475, A144255, A242330, A242331, A242332.
%K A360741 nonn,easy
%O A360741 1,1
%A A360741 _Elmo R. Oliveira_, Feb 18 2023