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A129612
Signature-permutation of a Catalan automorphism, row 251 of A089840.
4
0, 1, 3, 2, 7, 8, 6, 4, 5, 17, 18, 20, 21, 22, 16, 19, 14, 9, 10, 15, 11, 13, 12, 45, 46, 48, 49, 50, 54, 55, 57, 58, 59, 61, 62, 63, 64, 44, 47, 53, 56, 60, 42, 51, 37, 23, 24, 38, 25, 26, 27, 43, 52, 39, 28, 29, 41, 33, 35, 36, 40, 30, 34, 31, 32, 129, 130, 132, 133, 134
OFFSET
0,3
COMMENTS
Automorphism *A089863 = SPINE(*A129612). See the definition given in A122203.
PROG
(Constructive and destructive Scheme implementation of this automorphism. These act on S-expressions, i.e. list-structures:)
(define (*A129612 s) (cond ((pair? s) (let ((t (*A089863 s))) (cons (car t) (*A089859 (cdr t))))) (else s)))
(define (*A129612! s) (cond ((pair? s) (*A089863! s) (*A089859! (cdr s)))) s)
CROSSREFS
Inverse: A129611. Differs from A082345 for the first time at n=49, where A082345(49)=27, while a(49)=26.
Sequence in context: A130928 A154126 A069770 * A154455 A082345 A122327
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 22 2007
STATUS
approved