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A127287 Signature-permutation of a Catalan automorphism: composition of A127285 and A057508. 8
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 10, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 28, 24, 30, 33, 25, 29, 26, 31, 32, 27, 34, 35, 36, 37, 39, 38, 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, 65, 79, 67, 84, 93, 66, 80 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

This automorphism permutes the top-level of a list of even length (1 ... 2n) as (1 2n 2 2n-1 3 2n-3 ... n n+1) and when applied to a list of odd length (1 .. 2n+1), permutes it as (1 2n+1 2 2n 3 2n-1 ... n n+1). Used to construct A127291.

LINKS

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

Index entries for signature-permutations of Catalan automorphisms

PROG

(Scheme implementation of this automorphism, destructive, that acts on S-expressions, i.e. list-structures:)

(define (*A127287! s) (*A127285! (*A057508! s)))

CROSSREFS

Inverse: A127288. a(n) = A127285(A057508(n)).

Sequence in context: A261333 A031086 A127288 * A239088 A162344 A283962

Adjacent sequences:  A127284 A127285 A127286 * A127288 A127289 A127290

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jan 16 2007

STATUS

approved

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Last modified October 15 15:14 EDT 2019. Contains 328030 sequences. (Running on oeis4.)