A300130 Number of Motzkin trees that are a "uniquely typable skeleton".

0, 1, 0, 0, 2, 0, 1, 7, 1, 13, 34, 20, 100, 226, 234, 853, 1877, 2650, 8128, 18116, 30483, 85713

Offset

0,5

Comments

From the Bodini-Tarau paper: "A uniquely typable skeleton is one for which it exists exactly one simply-typed closed lambda term having it as a skeleton."

Links

Table of n, a(n) for n=0..21.

Olivier Bodini, Paul Tarau, On Uniquely Closable and Uniquely Typable Skeletons of Lambda Terms, arXiv:1709.04302 [cs.PL], 2017.

Crossrefs

Cf. A000108, A001006, A135501.

Sequence in context: A176129 A362787 A341200 * A101371 A325754 A154974

Adjacent sequences: A300127 A300128 A300129 * A300131 A300132 A300133

Keyword

nonn,more

Author

Michael De Vlieger, Feb 25 2018

Status

approved