A123498 Signature permutation of a nonrecursive Catalan automorphism: row 1654249 of table A089840.

0, 1, 2, 3, 4, 7, 5, 6, 8, 9, 10, 17, 16, 18, 11, 20, 12, 14, 15, 13, 19, 21, 22, 23, 24, 25, 26, 27, 45, 46, 44, 42, 43, 48, 47, 49, 50, 28, 29, 54, 53, 55, 30, 57, 31, 37, 38, 32, 39, 40, 41, 33, 61, 34, 51, 52, 35, 56, 58, 59, 36, 60, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71

Offset

0,3

Links

Table of n, a(n) for n=0..71.

A. Karttunen, Prolog-program which illustrates the construction of this and other similar nonrecursive Catalan automorphisms.

Index entries for signature-permutations of Catalan automorphisms

Prog

(Scheme) ;; Function, destructive implementation of this automorphism acting on S-expressions:
(define (*A123498! s) (cond ((null? s) s) ((and (pair? (cdr s)) (pair? (cadr s))) (let ((old-cddr-s (cddr s))) (set-cdr! (cdr s) (cdadr s)) (set-cdr! (cadr s) old-cddr-s)) (*A074679! s)) ((pair? (cdr s)) (*A072796! s)) ((pair? (car s)) (*A072797! s))) s)

Crossrefs

Inverse: A123497. Row 1654249 of A089840. Used to construct automorphism *A123502. A074679(n) = A083927(a(A057123(n))).

Sequence in context: A035532 A176535 A251716 * A123502 A073209 A073197

Adjacent sequences: A123495 A123496 A123497 * A123499 A123500 A123501

Keyword

nonn

Author

Antti Karttunen, Oct 11 2006

Status

approved