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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.

A245590 Primes p such that p^2 + 6 is a semiprime.

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%I A245590 #10 Aug 09 2014 23:08:41
%S A245590 2,3,7,17,23,41,47,53,59,101,149,157,173,179,193,211,229,233,239,241,
%T A245590 251,311,347,349,353,359,373,379,383,389,409,421,439,443,457,479,499,
%U A245590 509,521,541,571,577,599,619,641,661,691,701,719,751,761,769,809,823,829
%N A245590 Primes p such that p^2 + 6 is a semiprime.
%H A245590 K. D. Bajpai, <a href="/A245590/b245590.txt">Table of n, a(n) for n = 1..11200</a>
%e A245590 7 is in the sequence because it is prime and 7^2 + 6 = 55 = 5 * 11, which is semiprime.
%e A245590 23 is in the sequence because it is prime and 23^2 + 6 = 535 = 5 * 107, which is semiprime.
%p A245590 with(numtheory):A245590:=n->`if`(isprime(n) and bigomega(n^2+6)=2, n, NULL): seq(A245590 (n), n=1..1500);
%t A245590 Select[Prime[Range[200]], PrimeOmega[#^2 + 6] == 2 &]
%o A245590 (PARI)
%o A245590 forprime(p=1,10^4,if(bigomega(p^2+6)==2,print1(p,", "))) \\ _Derek Orr_, Aug 03 2014
%Y A245590 Cf. A000040, A001358.
%Y A245590 Cf. A109953 (primes p: p^2 + 2 is semiprime).
%Y A245590 Cf. A243365 (primes p: p^2 + 6 and p^2 - 6  are semiprimes).
%K A245590 nonn,easy
%O A245590 1,1
%A A245590 _K. D. Bajpai_, Jul 26 2014