%I #33 Oct 29 2023 01:51:57
%S 17,53,107,179,269,503,647,809,1187,1637,1889,2447,2753,3779,4157,
%T 4967,5399,5849,6317,6803,7307,7829,8369,10709,11987,12653,13337,
%U 14759,15497,16253,17027,19457,26729,29753,31859,32939,35153,38609,42227,44729,47303,52667,55457,61253,65789,68903,70487,72089,73709,75347
%N Primes of the form k+(k+3)^2 where k is a nonnegative integer.
%C Primes > 3 in A014209. - _Klaus Purath_, Dec 10 2020
%p A248697:=n->`if`(isprime(n+(n+3)^2), n+(n+3)^2, NULL): seq(A248697(n), n=1..5*10^2); # _Wesley Ivan Hurt_, Oct 11 2014
%t f[x_] := x + (x + 3)^2;
%t n = 50; result = {}; counter = 0; number = 0;
%t While[counter < n,
%t value = f[number];
%t If[PrimeQ[value] == True, AppendTo[result, value];counter = counter + 1];
%t number = number + 1];result
%t Select[Table[n + (n + 3)^2, {n, 0, 300}], PrimeQ] (* _Vincenzo Librandi_, Oct 12 2014 *)
%o (Magma) [a: n in [0..250] | IsPrime(a) where a is n^2+7*n+9]; // _Vincenzo Librandi_, Oct 12 2014
%o (PARI) for(n=1,10^3,if(isprime(n^2+7*n+9),print1(n^2+7*n+9,", "))) \\ _Derek Orr_, Oct 12 2014
%Y Cf. A014209.
%K nonn,easy
%O 1,1
%A _Michael Savoric_, Oct 11 2014
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