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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.

A242333 Numbers k such that k^2 + 5 is a semiprime.

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%I A242333 #11 Sep 08 2022 08:46:08
%S A242333 1,2,3,4,8,9,14,18,21,22,24,26,27,28,30,33,42,44,51,54,57,58,62,63,64,
%T A242333 68,69,82,84,86,90,93,98,99,102,104,108,111,118,132,134,138,144,152,
%U A242333 154,156,166,174,177,180,183,184,186,188,189,194,208,210,212,216
%N A242333 Numbers k such that k^2 + 5 is a semiprime.
%C A242333 The semiprimes of this form are: 6, 9, 14, 21, 69, 86, 201, 329, 446, 489, 581, 681, 734, 789, 905, 1094, 1769, 1941, 2606, 2921, 3254, ...
%H A242333 Vincenzo Librandi, <a href="/A242333/b242333.txt">Table of n, a(n) for n = 1..1000</a>
%t A242333 Select[Range[0, 300], PrimeOmega[#^2 + 5] == 2 &]
%o A242333 (Magma) IsSemiprime:=func<i | &+[d[2]: d in Factorization(i)] eq 2>; [n: n in [0..300] | IsSemiprime(s) where s is n^2+5];
%Y A242333 Cf. A056905, A078402, A085722, A242330, A242331, A242332.
%K A242333 nonn,easy
%O A242333 1,2
%A A242333 _Vincenzo Librandi_, May 14 2014