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 A072766 #11 Oct 25 2024 19:13:19 %S A072766 0,1,2,3,4,6,7,5,14,16,8,9,15,42,19,17,10,37,43,51,44,18,11,38,121,52, %T A072766 126,47,20,12,39,122,149,127,135,53,21,13,40,123,150,385,136,154,56, %U A072766 22,23,41,124,151,386,413,155,163,60,45,24,107,125,152,387,414,475,164 %N A072766 Transpose of A072764, 'cons' with arguments swapped. %H A072766 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (with the complete Scheme source) %H A072766 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %o A072766 (Scheme function showing the general idea:) (define (A072766 n) (cond ((zero? n) n) (else (let ((y (A025581 (-1+ n))) (x (A002262 (-1+ n)))) (CatalanRankGlobal (parenthesization->binexp (cons (binexp->parenthesization (A014486 x)) (binexp->parenthesization (A014486 y))))))))) %Y A072766 Inverse permutation: A072767. a(n) = A069770(A072764(n)). Also transpose of A072764, i.e. a(n) = A072764(A038722(n)). Projection functions are A072772 & A072771. The sizes of the corresponding Catalan structures: A072768. The first column: A057548, the first row: A072795. Cf. also A025581, A002262. %K A072766 nonn,tabl %O A072766 0,3 %A A072766 _Antti Karttunen_, Jun 12 2002 %E A072766 a(0)=0 prepended by _Sean A. Irvine_, Oct 25 2024