|
| |
|
|
A003227
|
|
Endpoints (leaves) in rooted trees with n nodes.
(Formerly M2744)
|
|
4
| |
|
|
1, 1, 3, 8, 22, 58, 160, 434, 1204, 3341, 9363, 26308, 74376, 210823, 599832, 1710803, 4891876, 14015505, 40231632, 115669419, 333052242, 960219982, 2771707332, 8009222307, 23166563032, 67069289457, 194332834601
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,3
|
|
|
REFERENCES
| R. W. Robinson and A. J. Schwenk, The distribution of trees in a large random tree, Discr. Math., 12 (1975), 359-.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
|
LINKS
| Index entries for sequences related to rooted trees
Index entries for sequences related to trees
Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.
|
|
|
FORMULA
| a(n)=sum{k=1 to n} k*A055277(n, k)
|
|
|
CROSSREFS
| Cf. A000081, A003228, A055277.
Sequence in context: A027243 A110239 A001853 * A077848 A055887 A024581
Adjacent sequences: A003224 A003225 A003226 * A003228 A003229 A003230
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| Corrected and extended with formula by Christian G. Bower (bowerc(AT)usa.net), May 25 2000
|
| |
|
|
