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 A072788 #6 May 01 2014 02:47:43 %S A072788 0,1,3,2,8,5,4,22,7,13,10,17,18,6,9,36,21,64,19,15,12,27,46,50,16,14, %T A072788 41,24,31,59,58,47,60,38,37,32,11,45,20,191,44,52,120,40,23,78,63,148, %U A072788 144,56,43,51,111,108,35,106,61,196,168,131,178,153,150,115,116,33,29 %N A072788 Inverse permutation to A072787. %H A072788 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> %H A072788 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %o A072788 (Scheme functions below show the essential idea. For a complete source, follow the "Gatomorphisms" link.) %o A072788 (define A072788 (arithrank->lexrank-bijection A072740 A072741)) %o A072788 (define (arithrank->lexrank-bijection pr1 pr2) (lambda (n) (CatalanRankGlobal (parenthesization->binexp (unrank-bintree n pr1 pr2))))) %o A072788 (define (unrank-bintree rank pr1 pr2) (cond ((zero? rank) (list)) (else (cons (unrank-bintree (pr1 (-1+ rank)) pr1 pr2) (unrank-bintree (pr2 (-1+ rank)) pr1 pr2))))) %Y A072788 Inverse permutation: A072787. Cf. also A072740, A072741, A072789. %K A072788 nonn,tabl %O A072788 0,3 %A A072788 _Antti Karttunen_, Jun 12 2002