%I A053526
%S A053526 0,0,0,0,16,110,435,1295,3220,7056,14070,26070,45540,75790,121121,
%T A053526 187005,280280,409360,584460,817836,1124040,1520190,2026255,2665355,
%U A053526 3464076,4452800,5666050,7142850,8927100,11067966,13620285
%N A053526 Number of bipartite graphs with 3 edges on nodes {1..n}.
%D A053526 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see
Problem 5.5.
%F A053526 (n-3)(n-2)(n-1)n(n^2+3n+4)/48.
%Y A053526 Cf. A000217 (1 edge), A050534 (2 edges).
%Y A053526 Sequence in context: A165558 A155871 A120668 this_sequence A107908 A144449
A000143
%Y A053526 Adjacent sequences: A053523 A053524 A053525 this_sequence A053527 A053528
A053529
%K A053526 nonn
%O A053526 0,5
%A A053526 N. J. A. Sloane (njas(AT)research.att.com), Jan 16 2000
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