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 A052291 #20 Jan 13 2024 11:45:58 %S A052291 2,3,5,7,13,37,47,67,73,103,157,163,193,233,317,337,547,587,647,653, %T A052291 677,683,773,827,883,887,947,983,1013,1063,1087,1163,1297,1327,1373, %U A052291 1487,1493,1523,1553,1567,1607,1627,1637,1657,1663,1667,1723,1867,1873 %N A052291 Primes p such that 4p^2 + 1 is also prime. %H A052291 T. D. Noe, <a href="/A052291/b052291.txt">Table of n, a(n) for n = 1..10000</a> %H A052291 Marek Wolf, <a href="http://arXiv.org/abs/0803.1456">Search for primes of the form m^2+1</a>, arXiv:0803.1456 [math.NT], 2008-2010. %e A052291 The 5th term is 13 and 4*169+1 = 677 is also a prime. %t A052291 Select[Prime[Range[300]],PrimeQ[4 #^2 + 1]&] (* _Vincenzo Librandi_, Apr 11 2013 *) %o A052291 (Magma) [p: p in PrimesUpTo(2000) | IsPrime(4*p^2+1)]; // _Vincenzo Librandi_, Apr 11 2013 %Y A052291 Cf. A052292. %K A052291 nonn,easy %O A052291 1,1 %A A052291 _Labos Elemer_, Feb 08 2000