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 A081725 #5 Mar 30 2012 18:39:16 %S A081725 1,2,4,3,5,5,7,7,6,8,15,7,10,10,9,8,11,10,11,14,13,14,13,11,12,15,16, %T A081725 20,21,13,14,14,17,13,16,16,16,17,17,17,20,16,20,22,26,19,13,15,19,21, %U A081725 21,25,21,21,21,21,25,25,27,31,27,20,22,26,28,20,21,17,21,23,24,22,22,22 %N A081725 A065560(n) + n - prime(n). %C A081725 Conjecture : a(n)>0 %K A081725 nonn %O A081725 1,2 %A A081725 _Benoit Cloitre_, Apr 06 2003