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 A072768 #6 Oct 25 2024 16:28:55 %S A072768 1,2,2,3,3,3,3,4,4,3,4,4,5,4,4,4,5,5,5,5,4,4,5,6,5,6,5,4,4,5,6,6,6,6, %T A072768 5,4,4,5,6,6,7,6,6,5,4,5,5,6,6,7,7,6,6,5,5,5,6,6,6,7,7,7,6,6,6,5,5,6, %U A072768 7,6,7,7,7,7,6,7,6,5,5,6,7,7,7,7,7,7,7,7,7,6,5,5,6,7,7,8,7,7,7,7,8,7,7,6,5 %N A072768 The RASTxx transformation of the sequence A072643. %C A072768 Also, the sizes of the parenthesizations produced by 'cons' combination A072764 and its transpose A072766. %C A072768 Differs from A071673 first time at the position n=37, where A072768(37) = 4, while A071673(37) = 5. RASTxx(A072768) differs from A071673 first time at the position n=704, which leads to conjecture that the repeated applications of RASTxx starting from A072643 converge towards A071673, the fixed point of RASTxx transformation. %C A072768 Each value v occurs A000108(v) times. (The term a(0)=0 is not explicitly listed here as to get a better looking triangle). %H A072768 A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms</a> (Includes the complete Scheme source for computing this sequence) %H A072768 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a> (Maple code for RASTxx transform) %o A072768 (Scheme) (define (A072768 n) (cond ((zero? n) n) (else (+ 1 (A072643 (A025581 (-1+ n))) (A072643 (A002262 (-1+ n))))))) %Y A072768 Same triangle computed modulo 2: A072770. Permutations: A072643, A071673, A072644, A072645, A072660, A072789. Cf. also A072769, A025581, A002262. %K A072768 nonn,tabl %O A072768 1,2 %A A072768 _Antti Karttunen_, Jun 12 2002