A130376 Signature permutation of a Catalan automorphism: apply *A074686 after the first nil on the top-level of list, if any present, otherwise leave the structure intact.

0, 1, 2, 3, 5, 4, 6, 7, 8, 13, 12, 9, 10, 11, 14, 15, 16, 17, 18, 19, 20, 21, 22, 36, 35, 31, 32, 34, 24, 23, 25, 26, 27, 28, 29, 30, 33, 38, 37, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 106, 105, 100, 101, 104

Offset

0,3

Links

A. Karttunen, Table of n, a(n) for n = 0..2055

Index entries for signature-permutations of Catalan automorphisms

Prog

(Destructive Scheme implementation of this automorphism, which acts on S-expressions, i.e. list-structures:)
(define *A130376! (!APPLY-AFTER-FIRST-NIL *A074686!))
(define (!APPLY-AFTER-FIRST-NIL f!) (letrec ((g! (lambda (s) (cond ((pair? s) (if (pair? (car s)) (g! (cdr s)) (f! (cdr s))))) s))) g!))

Crossrefs

Inverse: A130375. a(n) = A130369(A074686(n)) = A074685(A130372(A074686(n))) = A130369(A130372(A130370(n))).

Sequence in context: A130341 A130944 A122341 * A130342 A130943 A122342

Adjacent sequences: A130373 A130374 A130375 * A130377 A130378 A130379

Keyword

nonn

Author

Antti Karttunen, Jun 05 2007

Status

approved