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%I #19 Jul 16 2022 11:53:54
%S 5,89,281,1321,2129,2861,3701,4649,6469,6869,9049,9521,10501,13729,
%T 17389,18041,19381,21481,23689,26801,28429,33601,42169,71069,75041,
%U 81901,86161,90529,92009,101141,104281,113989,129361,131129,153281,157141,163021,169009,171029,200569,209441,213949,259169,274349,282101,314189,339389,371509,374501,383549,417649
%N Primes of the form x^2 + 5*y^2, where x and y=x+1 are consecutive natural numbers.
%C Terms are congruent to 1 mod 4.
%C Also primes of the form 6*x^2+10*x+5.
%C If one were to take the sum of all numbers in the open interval between n^2 and (n+1)^2 and called this sum A and did the same for (n+1)^2 and (n+2)^2 and called this sum B, then B-A is a prime, resulting from the same 6*n^2 + 10*n + 5. - J. M. Bergot, Jun 11 2011
%t Select[Table[x^2+5(x+1)^2,{x,0,500}],PrimeQ] (* _Harvey P. Dale_, Dec 16 2010 *)
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Apr 21 2010
%E Provided less ambiguous definition - _R. J. Mathar_, May 04 2010
%E More terms from _Vincenzo Librandi_ and _R. J. Mathar_, Apr 21 2010