

A283827


Irregular triangle read by rows: T(n,k) = number of trees on n nodes with load k, n>=1, 1 <= k <= floor(n/2).


1



0, 1, 1, 1, 1, 1, 2, 1, 2, 3, 1, 3, 7, 1, 3, 9, 10, 1, 4, 12, 30, 1, 4, 18, 38, 45, 1, 5, 21, 64, 144, 1, 5, 27, 91, 217, 210
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OFFSET

1,7


COMMENTS

The load of a tree is the maximal branch weight from the centroid.


LINKS

Table of n, a(n) for n=1..37.
Peter Steinbach, Field Guide to Simple Graphs, Volume 3, Part 8 (For Volumes 1, 2, 3, 4 of this book see A000088, A008406, A000055, A000664, respectively.)


EXAMPLE

Triangle begins:
0,
1,
1,
1, 1,
1, 2,
1, 2, 3,
1, 3, 7,
1, 3, 9, 10,
1, 4, 12, 30,
1, 4, 18, 38, 45,
1, 5, 21, 64, 144,
1, 5, 27, 91, 217, 210,
...


CROSSREFS

Cf. A283826.
See also A000676, A000677, A027416, A102911.
Sequence in context: A110062 A144215 A254539 * A122087 A139642 A264744
Adjacent sequences: A283824 A283825 A283826 * A283828 A283829 A283830


KEYWORD

nonn,tabf,more


AUTHOR

N. J. A. Sloane, Mar 19 2017


STATUS

approved



