A123494 Signature permutation of a Catalan automorphism: row 79361 of table A122202.

0, 1, 2, 3, 4, 8, 6, 7, 5, 9, 22, 20, 21, 10, 14, 19, 16, 17, 13, 15, 11, 12, 18, 23, 64, 62, 63, 24, 54, 61, 57, 58, 27, 55, 25, 26, 59, 37, 60, 53, 56, 38, 42, 51, 44, 45, 36, 41, 34, 35, 46, 43, 52, 39, 28, 33, 40, 30, 31, 50, 47, 29, 48, 49, 32, 65, 196, 194, 195, 66

Offset: 0

Author

Antti Karttunen, Oct 11 2006

Keywords

• nonn

Comments

This is the signature-permutation of Catalan automorphism which is derived from the automorphism *A123492 with the recursion schema KROF (defined in A122202). Like automorphisms *A057163 and *A069767/*A069768 these automorphisms are closed with respect to the subset of "zigzagging" binary trees (i.e., those binary trees where there are no nodes with two nonempty branches, or equivalently, those ones for which Stanley's interpretation (c) forms a non-branching line) and thus induce a permutation of binary strings. That is, starting from the root of such a binary tree, the turns taken by nonempty branches are interpreted as binary digits 0 or 1, depending on whether the tree grows to the left or right. In this manner, the Catalan automorphisms *A123494 and *A123493 induce the Binary Reflected Gray Code (see A003188 and A006068).

Links

• Index entries for signature-permutations of Catalan automorphisms

Crossrefs

Inverse: A123493. Row 79361 of A122202. See also A123715 and A123716.