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 A072767 #6 May 01 2014 02:47:42 %S A072767 0,1,2,3,4,7,5,6,10,11,16,22,29,37,8,12,9,15,21,14,28,36,45,46,56,67, %T A072767 79,92,106,121,137,154,172,191,211,232,254,17,23,30,38,47,13,18,20,55, %U A072767 66,27,78,91,105,19,25,35,120,136,44,153,171,190,54,210,231,253,276 %N A072767 Inverse permutation to A072766. %H A072767 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (with the complete Scheme source) %H A072767 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %o A072767 (Scheme function showing the general idea:) (define (A072767 n) (cond ((zero? n) n) (else (1+ (packA001477 (A072772 n) (A072771 n)))))) %Y A072767 Cf. A072765, A001477, A072771, A072772. %K A072767 nonn %O A072767 0,3 %A A072767 _Antti Karttunen_, Jun 12 2002