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 A088633 #4 Mar 30 2012 16:49:50 %S A088633 2,2,3,4,7,6,7,10,9,10,13,12,17,16,15,16,21,20,19,22,21,22,25,24,29, %T A088633 28,27,32,31,30,31,36,35,34,37,36,37,42,41,40,43,42,47,46,45,52,51,50, %U A088633 49,52,51,52,55,54,55,58,57,70,69,68,67,66,65,64,67,66,71,70,69,70,79,78,77,76 %N A088633 P-n where P = smallest prime > 2n. %p A088633 with(numtheory); A088633 := n->nextprime(2*n)-n; %Y A088633 Cf. A088631. %K A088633 nonn %O A088633 0,1 %A A088633 _N. J. A. Sloane_, Nov 24 2003