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%I #20 Feb 28 2018 04:59:36
%S 1,1,1,1,1,1,1,1,1,2,2,1,1,1,2,3,4,1,1,1,1,2,4,7,8,6,3,2,1,1,1,2,4,8,
%T 13,19,14,13,7,4,1,1,1,1,2,4,9,16,32,45,52,48,40,24,16,7,3,2,1,1,1,2,
%U 4,9,17,38,70,120,150,179,164,143,94,63,32,19,7,4,1,1,1,1,2,4,9,18,41,85,181,324,500,659
%N Triangle T(n,k) read by rows, giving number of bipartite graphs with n nodes (n >= 0) and k edges (0 <= k <= floor(n/2*n/2)).
%C The sum of the m-th row is the (m-1)-st member of A033995, number of bipartite graphs with n nodes.
%D F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, New York / London, 1973.
%H P. Hanlon, <a href="http://dx.doi.org/10.1016/0012-365X(79)90184-5">The enumeration of bipartite graphs</a>, Discrete Math. 28 (1979), 49-57.
%H Juergen Will, <a href="/A297877/a297877.txt">Rows 0 to 10 of triangle.</a>
%e Triangle begins:
%e 0: 1;
%e 1: 1;
%e 2: 1, 1;
%e 3: 1, 1, 1;
%e 4: 1, 1, 2, 2, 1;
%e 5: 1, 1, 2, 3, 4, 1, 1;
%e 6: 1, 1, 2, 4, 7, 8, 6, 3, 2, 1;
%e 7: 1, 1, 2, 4, 8, 13, 19, 14, 13, 7, 4, 1, 1;
%Y Cf. A033995 (row sums).
%K nonn,tabf
%O 0,10
%A _Juergen Will_, Jan 07 2018
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