A069889 - OEIS

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A069889

Self-inverse permutation of natural numbers induced by the automorphism RotateHandshakes_et_DeepReverse! acting on the parenthesizations encoded by A014486.

0, 1, 3, 2, 7, 8, 6, 4, 5, 17, 20, 18, 21, 22, 16, 19, 14, 9, 11, 15, 10, 12, 13, 45, 54, 48, 57, 61, 46, 55, 49, 58, 62, 50, 59, 63, 64, 44, 53, 47, 56, 60, 42, 51, 37, 23, 28, 39, 25, 30, 33, 43, 52, 38, 24, 29, 40, 26, 31, 34, 41, 27, 32, 35, 36, 129, 157, 138, 166, 180

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

COMMENTS

This automorphism reflects non-crossing handshakes (the interpretation n of Stanley's exercise 19) over the diagonal that goes through corner at "11 o'clock".

LINKS

Table of n, a(n) for n=0..69.

A. Karttunen, Gatomorphisms (Includes the complete Scheme program for computing this sequence)

R. P. Stanley, Exercises on Catalan and Related Numbers

Index entries for sequences that are permutations of the natural numbers

CROSSREFS

Composition of A057501 and A057164, i.e. A069888(n) = A057164(A057501(n)). Cf. also A069888.

Sequence in context: A154456 A122328 A082346 * A154451 A131000 A122351

Adjacent sequences: A069886 A069887 A069888 * A069890 A069891 A069892

KEYWORD

nonn

AUTHOR

Antti Karttunen, Apr 16 2002

STATUS

approved