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 A205721 #8 Mar 30 2012 18:58:11 %S A205721 2,4,2,6,8,5,4,7,5,11,2,6,9,4,7,12,2,6,9,14,8,10,5,11,13,4,7,12,15,5, %T A205721 11,13,18,2,6,9,14,16,8,10,17,2,6,9,14,16,21,8,10,17,22,4,7,12,15,19, %U A205721 5,11,13,18,20,2,6,9,14,16,21,23,4,7 %N A205721 The number j such that 10 divides prime(k)-prime(j), where k(n)=A205720(n). %C A205721 For a guide to related sequences, see A205558. %e A205721 (See the example at A205720.) %t A205721 (See the program at A205720.) %Y A205721 Cf. A204890, A205720, A205558. %K A205721 nonn %O A205721 1,1 %A A205721 _Clark Kimberling_, Jan 31 2012