%I #19 Oct 28 2021 07:10:09
%S 1,1,2,1,5,43,1,15,463,16372,1,50,5193,583199,65485654,1,175,58653,
%T 20788249,7354266811,2602065897364,1,625,663203,741026781,825905301851
%N Table read by rows: T(n,k) is the number of no-leaf subgraphs of the n X k grid where 1 <= k <= n.
%e Three of the T(4,3) = 463 subgraphs of the 4 X 3 grid with no leaf vertices are
%e + +---+ + + + + +---+
%e | | | |
%e +---+---+ +---+---+ + +---+
%e | | , | | |, and .
%e +---+ + + +---+ +---+ +
%e | | | | | |
%e +---+ + +---+ + +---+ +
%e Table begins:
%e n\k| 1 2 3 4 5 6
%e ---+---------------------------------------------------
%e 1 | 1
%e 2 | 1 2
%e 3 | 1 5 43
%e 4 | 1 15 463 16372
%e 5 | 1 50 5193 583199 65485654
%e 6 | 1 175 58653 20788249 7354266811 2602065897364
%Y Cf. A093129, A301976, A320097, A320099.
%K nonn,tabl,more
%O 1,3
%A _Peter Kagey_, Oct 05 2018
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