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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified April 12 22:36 EDT 2021. Contains 342933 sequences. (Running on oeis4.)