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 A248409 #14 Oct 08 2014 16:53:29
%S A248409 13,53,181,233,389,757,641,857,1069,1301,1609,1873,2213,2549,3121,
%T A248409 3329,3761,4261,4729,5209,5737,6301,6977,7489,8161,8837,9733,10193,
%U A248409 10937,11701,12497,13313,14173,15053,16069,17137,18121,18773,19777,20809,21997,23053,24137,25169,27109,27509
%N A248409 Least prime of the form x^2+13*n^2.
%C A248409 Subsequence of A033210 (Primes of the form x^2+13*y^2).
%H A248409 Jens Kruse Andersen, <a href="/A248409/b248409.txt">Table of n, a(n) for n = 1..10000</a>
%e A248409 a(1)=13 because the least prime of the form x^2+13*1^2 is 13 (at x=0).
%e A248409 a(100)=130121 because the least prime of the form x^2+13*100^2 is 130121 (at x=11).
%e A248409 a(200)=520361 because the least prime of the form x^2+13*200^2 is 520361 (at x=19).
%o A248409 (PARI) a(n) = {x = 0; while (!isprime(p=x^2+13*n^2), x++); p;} \\ _Michel Marcus_, Oct 06 2014
%Y A248409 Cf. A033210, A106856, A247881, A248221.
%K A248409 nonn
%O A248409 1,1
%A A248409 _Zak Seidov_, Oct 06 2014