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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A074684 Permutation of natural numbers induced by Catalan Automorphism *A074684 acting on the parenthesizations encoded by A014486/A063171.

Original entry on oeis.org

0, 1, 3, 2, 8, 7, 5, 4, 6, 22, 21, 18, 17, 20, 13, 12, 10, 9, 11, 15, 14, 19, 16, 64, 63, 59, 58, 62, 50, 49, 46, 45, 48, 55, 54, 61, 57, 36, 35, 32, 31, 34, 27, 26, 24, 23, 25, 29, 28, 33, 30, 41, 40, 38, 37, 39, 52, 51, 60, 56, 43, 42, 47, 44, 53, 196, 195, 190, 189, 194
Offset: 0

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Author

Antti Karttunen, Sep 11 2002

Keywords

Comments

This bijection maps between the "standard" ordering of binary trees as encoded by A014486 and "variant A quaternary encoding" as explained in the sequence A085184.
This is a rare example of a simply defined Catalan Automorphism where the cycle count sequence (A089411) is not monotone. (See A127296 for a much more complex example.)

Crossrefs

Row 17 of A122201. Inverse of A074683. a(n) = A057163(A074681(A057163(n))).
The number of cycles, maximum cycle sizes and LCM's of all cycle sizes in subpermutations limited by A014137 and A014138 are given by A089411, A086586 and A089412.