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 A123696 Signature permutation of a nonrecursive Catalan automorphism: row 1653063 of table A089840. 4
 0, 1, 3, 2, 8, 7, 4, 5, 6, 21, 22, 17, 18, 20, 9, 10, 11, 12, 13, 14, 15, 16, 19, 58, 59, 62, 63, 64, 45, 46, 48, 49, 50, 54, 55, 57, 61, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 47, 51, 52, 53, 56, 60, 170, 171, 174, 175, 176 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS This automorphism is illustrated below, where letters A, B and C refer to arbitrary subtrees located on those nodes and () stands for an implied terminal node. ............................B...C.......C...D.............................. .............................\./.........\./............................... .A...B.............B...C......x...D....B..x............()...C......C..()... ..\./...............\./........\./......\./.............\./.........\./.... ...x...C..-->....A...x......()..x...-->..x..().......()..x....-->....x..(). ....\./...........\./........\./..........\./.........\./.............\./.. .....x.............x..........x............x...........x...............x... See the comments at A123695. LINKS PROG (Scheme function, destructive implementation of this automorphism acting on S-expressions:) (define (*A123696! s) (cond ((null? s) s) ((pair? (car s)) (*A074680! s)) ((pair? (cdr s)) (*A074680! (cdr s)) (*A069770! s))) s) CROSSREFS Inverse: A123695. Row 1653063 of A089840. Variant of A074680. Sequence in context: A245781 A239803 A083514 * A123500 A074689 A122331 Adjacent sequences:  A123693 A123694 A123695 * A123697 A123698 A123699 KEYWORD nonn AUTHOR Antti Karttunen, Oct 11 2006 STATUS approved

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Last modified December 12 17:59 EST 2019. Contains 329960 sequences. (Running on oeis4.)