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.
%I A216968 #20 Sep 08 2022 08:46:04
%S A216968 0,1,2,5,7,8,22,23,28,37,40,43,47,50,55,62,70,82,83,92,98,103,107,110,
%T A216968 113,118,125,127,128,133,160,170,175,187,197,202,203,205,208,212,247,
%U A216968 250,253,265,268,275,278,320,322,352,370,373,377,380,407,412,413,415
%N A216968 Numbers n such that 2*n^2 + 3 is prime.
%H A216968 Zak Seidov, <a href="/A216968/b216968.txt">Table of n, a(n) for n = 1..10000</a>
%p A216968 a:= proc(n) option remember; local k;
%p A216968 for k from 1+ `if`(n=1, -1, a(n-1))
%p A216968 while not isprime(2*k^2 + 3) do od; k
%p A216968 end:
%p A216968 seq(a(n), n=1..100); # _Alois P. Heinz_, Sep 23 2012
%t A216968 p=3; s3={}; Do[If[PrimeQ[p + 2 n^2], AppendTo[s3, n]], {n, 0, 500}]
%t A216968 Select[Range[0,500],PrimeQ[2#^2+3]&] (* _Harvey P. Dale_, Nov 24 2013 *)
%o A216968 (Magma) [n: n in [0..500] | IsPrime(2*n^2+3)]; // _Bruno Berselli_, Sep 21 2012
%o A216968 (PARI) select(n->isprime(2*n^2+3),vector(2000,n,n-1)) /* _Joerg Arndt_, Sep 21 2012 */
%Y A216968 Cf. A201473 (associated primes), A216898.
%K A216968 nonn,easy
%O A216968 1,3
%A A216968 _Zak Seidov_, Sep 20 2012