6 citations · 20 across the 12 of their papers we have counts for
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A De Bruijn-Erdős theorem in graphs?
Vašek Chvátal
A set of points in the Euclidean plane determines at least distinct lines unless these points are collinear. In 2006, Chen and Chvátal asked whether the same statement…
A De Bruijn-Erdos theorem for 1-2 metric spaces
Vasek Chvatal
A special case of a combinatorial theorem of De Bruijn and Erdos asserts that every noncollinear set of n points in the plane determines at least n distinct lines. Chen and Chvatal…
A De Bruijn-Erdos theorem for chordal graphs
Laurent Beaudou, Adrian Bondy, Xiaomin Chen +5
A special case of a combinatorial theorem of De Bruijn and Erdos asserts that every noncollinear set of n points in the plane determines at least n distinct lines. Chen and Chvatal…
Lines in hypergraphs
Laurent Beaudou, Adrian Bondy, Xiaomin Chen +5
One of the De Bruijn - Erdos theorems deals with finite hypergraphs where every two vertices belong to precisely one hyperedge. It asserts that, except in the perverse case where a…
Finite Sholander Trees, Trees, and their Betweenness
Vašek Chvátal, Dieter Rautenbach, Philipp Matthias Schäfer
We provide a proof of Sholander's claim (Trees, lattices, order, and betweenness, Proc. Amer. Math. Soc. 3, 369-381 (1952)) concerning the representability of collections of so-cal…
Comparison of two techniques for proving nonexistence of strongly regular graphs
Vasek Chvatal
We show that the method of counting closed walks in strongly regular graphs rules out no parameter sets other than those ruled out by the method of counting eigenvalue multipliciti…