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%I #13 Sep 08 2022 08:45:01
%S 7,31,127,367,631,967,1231,3727,4231,6247,7927,8287,11887,17167,21031,
%T 22807,30631,34231,39607,48847,72367,108247,109567,126031,160807,
%U 185767,198031,231367,235231,261127,265231,279847,290527,323767,354031
%N Primes of the form k^2+6.
%C a(n) mod 120 = 7 or 31 for all n.
%H Vincenzo Librandi, <a href="/A056909/b056909.txt">Table of n, a(n) for n = 1..2400</a>
%F a(n) = 36*A056910(n)^2 + 12*A056910(n) + 7.
%e a(2)=127 since 11^2+6=127 which is prime.
%t Intersection[Table[n^2+6,{n,0,10^2}],Prime[Range[9*10^3]]] ...or... For[i=6,i<=6,a={};Do[If[PrimeQ[n^2+i],AppendTo[a,n^2+i]],{n,0,100}];Print["n^2+",i,",",a];i++ ] - _Vladimir Joseph Stephan Orlovsky_, Apr 29 2008
%t Select[Table[n^2+6,{n,0,7000}],PrimeQ] (* _Vincenzo Librandi_, Nov 30 2011 *)
%o (Magma) [a: n in [0..700] | IsPrime(a) where a is n^2+6]; // _Vincenzo Librandi_, Nov 30 2011
%Y Cf. A002496, A056899, A049423, A005473, A056905.
%K nonn,easy
%O 1,1
%A _Henry Bottomley_, Jul 07 2000
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