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A130918 Simple self-inverse permutation of natural numbers: List each block of A000108(n) numbers from A014137(n-1) to A014138(n-1) in reverse order. +0
2
0, 1, 3, 2, 8, 7, 6, 5, 4, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 196, 195, 194, 193, 192 (list; graph; listen)
OFFSET

0,3

COMMENT

In principle this involution is the signature permutation of yet another Catalan automorphism. However, the question remains what is the most "natural" way to create such an automorphism acting e.g. on S-expressions (i.e. rooted plane binary trees), which would produce this sequence as its signature permutation.

LINKS

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

Index entries for signature-permutations of Catalan automorphisms

FORMULA

a(0)=0, a(n) = A014138(A072643(n)-1) - A082853(n).

PROGRAM

(Scheme:) (define (A130918 n) (if (zero? n) n (- (A014138 (- (A072643 n) 1)) (A082853 n))))

CROSSREFS

Inverse: A130918. Cf. A054429, A057163. The number of cycles and the number of fixed points in range [A014137(n-1)..A014138(n-1)] of this permutation are given by A130380 and A036987.

Sequence in context: A082348 A122339 A057163 this_sequence A021308 A060921 A095013

Adjacent sequences: A130915 A130916 A130917 this_sequence A130919 A130920 A130921

KEYWORD

nonn

AUTHOR

Antti Karttunen (His-Firstname.His-Surname(AT)gmail.com), Jun 11 2007

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Last modified November 30 22:12 EST 2008. Contains 150989 sequences.


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