A123497 Signature permutation of a nonrecursive Catalan automorphism: row 1655089 of table A089840.

0, 1, 2, 3, 4, 6, 7, 5, 8, 9, 10, 14, 16, 19, 17, 18, 12, 11, 13, 20, 15, 21, 22, 23, 24, 25, 26, 27, 37, 38, 42, 44, 47, 51, 53, 56, 60, 45, 46, 48, 49, 50, 31, 32, 30, 28, 29, 34, 33, 35, 36, 54, 55, 40, 39, 41, 57, 43, 58, 59, 61, 52, 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 (*A123497! s) (cond ((null? s) s) ((and (pair? (car s)) (pair? (cdar s))) (*A074680! s) (let ((old-cddr-s (cddr s))) (set-cdr! (cdr s) (cdadr s)) (set-cdr! (cadr s) old-cddr-s))) ((pair? (car s)) (*A072797! s)) ((pair? (cdr s)) (*A072796! s))) s)

Crossrefs

Inverse: A123498. Row 1655089 of A089840. Used to construct automorphism *A123501. A074680(n) = A083927(a(A057123(n))).

Sequence in context: A344412 A143102 A013944 * A123501 A073210 A073196

Adjacent sequences: A123494 A123495 A123496 * A123498 A123499 A123500

Keyword

nonn

Author

Antti Karttunen, Oct 11 2006

Status

approved