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 A023252 #24 Mar 14 2025 15:51:49 %S A023252 13,19,31,79,97,199,331,349,373,457,541,577,607,643,709,769,811,859, %T A023252 1021,1069,1171,1249,1321,1381,1447,1483,1693,1867,2113,2137,2239, %U A023252 2539,2719,3037,3061,3163,3181,3187,3313,3433,3463,3673,3727,3853,3919,4021,4639 %N A023252 Primes that remain prime through 2 iterations of function f(x) = 5x + 2. %C A023252 Primes p such that 5*p+2 and 25*p+12 are also primes. - _Vincenzo Librandi_, Aug 04 2010 %H A023252 Harvey P. Dale, <a href="/A023252/b023252.txt">Table of n, a(n) for n = 1..1000</a> %t A023252 Select[Prime[Range[1000]],And@@PrimeQ[NestList[5#+2&,#,2]]&] (* _Harvey P. Dale_, Nov 24 2012 *) %o A023252 (Magma) [n: n in [0..100000] | IsPrime(n) and IsPrime(5*n+2) and IsPrime(25*n+12)]; // _Vincenzo Librandi_, Aug 04 2010 %K A023252 nonn %O A023252 1,1 %A A023252 _David W. Wilson_