A063682 Number of 2-trees rooted at an asymmetric end-edge.

0, 1, 3, 13, 52, 229, 1024, 4749, 22454, 108299, 529896, 2625903, 13148268, 66428383, 338197609, 1733399552, 8936746984, 46315049443, 241146306914, 1260805087503, 6616786338256, 34843842405490, 184057255372576

Offset

1,3

References

F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 75, Eq. (3.5.4).

Links

Table of n, a(n) for n=1..23.

Crossrefs

Cf. A058870, A058866, A054581.

Sequence in context: A037772 A037660 A122600 * A346409 A082376 A065059

Adjacent sequences: A063679 A063680 A063681 * A063683 A063684 A063685

Keyword

nonn

Author

Vladeta Jovovic, Aug 22 2001

Status

approved