A320101 Table read by rows: T(n,k) is the number of no-leaf subgraphs of the n X k grid where 1 <= k <= n.

1, 1, 2, 1, 5, 43, 1, 15, 463, 16372, 1, 50, 5193, 583199, 65485654, 1, 175, 58653, 20788249, 7354266811, 2602065897364, 1, 625, 663203, 741026781, 825905301851

Offset: 1

Author

Peter Kagey, Oct 05 2018

Keywords

• nonn
• tabl
• more

Examples

			Three of the T(4,3) = 463 subgraphs of the 4 X 3 grid with no leaf vertices are
  +   +---+      +   +   +      +   +---+
      |   |                         |   |
  +---+---+      +---+---+      +   +---+
  |   |    ,     |   |   |, and          .
  +---+   +      +   +---+      +---+   +
  |   |          |   |          |   |
  +---+   +      +---+   +      +---+   +
Table begins:
  n\k|    1    2     3        4          5             6
  ---+---------------------------------------------------
   1 |    1
   2 |    1    2
   3 |    1    5    43
   4 |    1   15   463    16372
   5 |    1   50  5193   583199   65485654
   6 |    1  175 58653 20788249 7354266811 2602065897364
		

Crossrefs

Cf. A093129, A301976, A320097, A320099.