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 A102451 #6 Mar 30 2012 18:50:48 %S A102451 1,2,3,4,5,7,6,8,9,11,10,13,12,16,14,15,17,19,18,23,20,21,22,25,24,27, %T A102451 26,29,28,31,32,30,37,33,34,35,36,41,38,39,40,43,47,42,44,45,46,49,48, %U A102451 53,50,51,52,59,54,55,56,57,58,61,64,60,62,63,67,65,71,66,68,69,73,70 %N A102451 Inverse of A100806. %H A102451 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %K A102451 nonn %O A102451 1,2 %A A102451 _Reinhard Zumkeller_, Jan 09 2005