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 A002971 M0587 #29 Oct 20 2023 22:00:27 %S A002971 1,2,3,4,8,9,11,12,13,14,16,17,18,21,23,26,29,34,36,37,38,47,48,49,51, %T A002971 53,54,56,62,63,66,67,68,69,73,74,77,79,82,83,91,99,101,102,103,107, %U A002971 108,114,116,118,122,131,134,141,142,147,148,151,154,156,157,158,159,164 %N A002971 Numbers k such that 4*k^2 + 25 is prime. %D A002971 E. Kogbetliantz and A. Krikorian, Handbook of First Complex Prime Numbers, Gordon and Breach, NY, 1971, p. 1. %D A002971 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A002971 T. D. Noe, <a href="/A002971/b002971.txt">Table of n, a(n) for n = 1..1000</a> %H A002971 E. Kogbetliantz and A. Krikorian <a href="/A002970/a002970.pdf">Handbook of First Complex Prime Numbers</a>, Gordon and Breach, NY, 1971 [Annotated scans of a few pages] %t A002971 Select[Range[200], PrimeQ[4 #^2 + 25] &] (* _Vincenzo Librandi_, Mar 19 2014 *) %o A002971 (Magma) [n: n in [0..600] |IsPrime(4*n^2+25)]; // _Vincenzo Librandi_, Nov 21 2010 %o A002971 (PARI) is(n)=isprime(4*n^2+25) \\ _Charles R Greathouse IV_, Jun 06 2017 %K A002971 nonn,easy %O A002971 1,2 %A A002971 _N. J. A. Sloane_