cp's OEIS Frontend

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.

A154124 Signature permutation of a Catalan bijection: row 3748 of A089840.

Original entry on oeis.org

0, 1, 2, 3, 6, 4, 5, 7, 8, 16, 19, 9, 10, 11, 15, 14, 12, 17, 18, 13, 20, 21, 22, 44, 47, 53, 56, 60, 23, 24, 25, 26, 27, 28, 29, 30, 33, 43, 52, 37, 38, 39, 40, 42, 31, 45, 46, 32, 48, 49, 50, 41, 51, 34, 54, 55, 35, 57, 58, 59, 36, 61, 62, 63, 64, 128, 131, 137, 140, 144
Offset: 0

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Author

Antti Karttunen, Jan 06 2009

Keywords

Comments

This bijection of binary trees is obtained in the following way. (Inverse of Thompson's B!):
.B...C...............C...D
..\./.................\./
...x...D....-->....B...x.................()..C ........A...()
....\./.............\./...................\./....-->....\./...
.A...x...........A...x.................A...x.........C...x....
..\./.............\./...................\./...........\./.....
...x...............x.....................x.............x......
..............................................................
That is, (a . ((b . c) . d)) -> (a . (b . (c . d)))
or (a . (() . c)) -> (c . (a . ())) if the former is not possible.

Crossrefs

Inverse: A154123. Cf. A154122.