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 A075161 #8 Apr 07 2015 04:26:47 %S A075161 0,1,2,3,4,5,9,7,6,10,23,12,65,24,11,8,197,15,626,26,25,66,2056,13,14, %T A075161 198,16,68,6918,29,23714,17,67,627,28,40,82500,2057,199,27,290512,71, %U A075161 1033412,200,30,6919,3707852,31,37,38,628,629,13402697,43,70,69,2058 %N A075161 Position of A075165(n+1) in A014486. %C A075161 See A075166. %H A075161 Antti Karttunen, <a href="/A075161/b075161.txt">Table of n, a(n) for n = 0..1024</a> %H A075161 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/ACO1.htm">Alternative Catalan Orderings</a> (with the complete Scheme source) %H A075161 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %o A075161 (Scheme functions showing the essential idea. For the complete source, follow the "Alternative Catalan Orderings" link:) %o A075161 (define (A075161 n) (CatalanRankGlobal (parenthesization->binexp (primefactorization->parenthesization (1+ n))))) %o A075161 (define (primefactorization->parenthesization n) (map primefactorization->parenthesization (explist->Nvector! (primefactorization->explist n)))) %o A075161 Function primefactorization->explist maps 1 to (), 2 to (1), 3 to (1 0), 4 to (2), 12 to (1 2), etc. %o A075161 (define (explist->Nvector! el) (cond ((pair? el) (let loop ((el (cdr el))) (cond ((pair? el) (set-car! el (1+ (car el))) (loop (cdr el))))))) el) %Y A075161 Inverse of A075162. a(n) = A075163(n+1)-1. Cf. A075168. %K A075161 nonn %O A075161 0,3 %A A075161 _Antti Karttunen_, Sep 13 2002