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 A055784 #10 Jun 14 2017 07:13:26 %S A055784 29,59,79,139,179,199,239,379,419,439,479,599,619,719,739,839,1019, %T A055784 1039,1279,1319,1399,1499,1579,1979,1999,2239,2339,2399,2579,2699, %U A055784 2719,2819,2939,3079,3119,3319,3499,3539,3739,4019,4099,4219,4339,4639,4679 %N A055784 Primes q of form q = 10p + 9, where p is also prime. %e A055784 5419 = 541*10 + 9, 9 is appended to 541. %t A055784 Select[10#+9&/@Prime[Range[100]],PrimeQ] (* _Harvey P. Dale_, Aug 20 2012 *) %Y A055784 Cf. A005384, A005385. %K A055784 nonn %O A055784 1,1 %A A055784 _Labos Elemer_, Jul 13 2000