A058519 Number of directed cycles of B-trees of order 3 with n labeled leaves.

0, 1, 2, 3, 5, 8, 15, 24, 46, 82, 157, 293, 576, 1095, 2138, 4156, 8162, 16019, 31675, 62608, 124341, 247224, 493067, 984905, 1971970, 3953749, 7941397, 15971775, 32168510, 64866564, 130959749, 264676274, 535488128, 1084424916

Offset

0,3

Links

Table of n, a(n) for n=0..33.

Maple

spec := [C, {B=Union(Z, Subst(M, B)), M=Union(Prod(Z, Z), Prod(Z, Z, Z)), C=Cycle(B)}]; [seq(combstruct[count](spec, size=n), n=0..40)];

Crossrefs

Cf. A058518, A014535.

Sequence in context: A102973 A371992 A066372 * A181065 A282239 A191792

Adjacent sequences: A058516 A058517 A058518 * A058520 A058521 A058522

Keyword

nonn

Author

N. J. A. Sloane, Dec 21 2000

Status

approved