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).

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

Author

N. J. A. Sloane, Mar 19 2017

Keywords

• nonn
• tabf
• more

Comments

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

Examples

			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,
  ...
		

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.)

Crossrefs

Cf. A283826.

See also A000676, A000677, A027416, A102911.