A080299 A014486-encoding of plane binary trees (Stanley's d) whose interior zigzag-tree (Stanley's c, i.e., tree obtained by discarding the outermost edges of the binary tree) is isomorphic to a valid plane binary tree (Stanley's d).

2, 50, 818, 914, 13106, 13202, 14642, 14738, 15506, 209714, 209810, 211250, 211346, 212114, 234290, 234386, 235826, 235922, 236690, 248114, 248210, 248978, 255122, 3355442, 3355538, 3356978, 3357074, 3357842, 3380018, 3380114, 3381554

Offset: 0

Author

Antti Karttunen, Mar 02 2003

Keywords

• nonn

Comments

These trees are obtained by replacing each non-root terminal node (a leaf) of the binary tree with a branch of two leaves, i.e., "." -> "\/".

Links

• A. Karttunen, Nine initial trees can be found here (The trees with the ordinal numbers 1., 6., 39., 53., 345., 359., 477., 491. and 567.)
• R. P. Stanley, Exercises on Catalan and Related Numbers

Crossrefs

a(n) = A014486(A080298(n)). Breadth-first-wise encoding: A080313.

Formula

a(n) = A080310(A014486(n)).