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 A263726 #12 Nov 07 2015 17:03:23
%S A263726 2,3,2,5,2,5,2,3,3,7,2,11,2,5,2,5,3,5,5,5,2,5,11,3,2,5,2,5,2,3,3,5,19,
%T A263726 2,5,2,13,7,3,11,11,2,3,13,3,11,2,29,2,5,3,5,2,5,5,7,7,3,11,2,11,2,3,
%U A263726 11,7,5,2,5,2,3,3,5,2,11,5,5,3,3,59,2,11,2,3,7,13,5,2,5,7
%N A263726 Least prime p such that p^2 + A263977(n)^2 is prime.
%C A263726 The least k, such that prime(n) is the smallest prime p for which k^2 + p^2 is also prime, is in A263466.
%H A263726 Stephan Baier and Liangyi Zhao, <a href="http://arxiv.org/abs/math/0703284">On Primes Represented by Quadratic Polynomials</a>, Anatomy of Integers, CRM Proc. & Lecture Notes, Vol. 46, Amer. Math. Soc. 2008, pp. 169 - 166.
%H A263726 Étienne Fouvry and Henryk Iwaniec, <a href="http://matwbn.icm.edu.pl/ksiazki/aa/aa79/aa7935.pdf">Gaussian primes</a>, Acta Arithmetica 79:3 (1997), pp. 249-287.
%e A263726 A263977(1) = 1, and 2 and 2^2 + 1^2 = 5 are prime, so a(1) = 2.
%t A263726 f[n_] := Block[{p = 2}, While[! PrimeQ[n^2 + p^2] && p < 1500, p = NextPrime@ p]; If[p > 1500, 0, p]]; lst = {}; k = 1; While[k < 130, If[f@ k > 0, AppendTo[lst, f@ k]]; k++]; lst
%Y A263726 Cf. A240130, A240131, A263466, A263722, A263977.
%K A263726 nonn
%O A263726 1,1
%A A263726 _Jonathan Sondow_ and _Robert G. Wilson v_, Oct 30 2015