A089417 Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A082333/A082334.

1, 1, 1, 2, 7, 6, 10, 20, 37, 70, 130, 272, 480, 954, 1750, 3462, 6481, 12922, 24372, 48702, 92490

Offset

0,4

Comments

The number of orbits to which the corresponding automorphism(s) partitions the set of A000108(n) binary trees with n internal nodes.

Is the non-monotone notch from a(4)=7 to a(5)=6 the only one?

Links

Table of n, a(n) for n=0..20.

A. Karttunen, C-program for computing the initial terms of this sequence

Crossrefs

Cf. A089411.

Sequence in context: A217568 A320871 A154200 * A168205 A265495 A338041

Adjacent sequences: A089414 A089415 A089416 * A089418 A089419 A089420

Keyword

nonn

Author

Antti Karttunen, Nov 29 2003, Proposed by Wouter Meeussen, Spring 2003.

Status

approved