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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
OFFSET
1,7
COMMENTS
The load of a tree is the maximal branch weight from the centroid.
LINKS
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.
Sequence in context: A110062 A144215 A254539 * A122087 A139642 A264744
KEYWORD
nonn,tabf,more
AUTHOR
N. J. A. Sloane, Mar 19 2017
STATUS
approved