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A123497
Signature permutation of a nonrecursive Catalan automorphism: row 1655089 of table A089840.
5
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
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
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 11 2006
STATUS
approved