6 citations · 20 across the 12 of their papers we have counts for
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math.CO2009★ 2 cited
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…
math.CO2009
A de Bruijn - Erdős theorem and metric spaces
Ehsan Chiniforooshan, Vašek Chvátal
De Bruijn and Erdős proved that every noncollinear set of n points in the plane determines at least n distinct lines. Chen and Chvátal suggested a possible generalization of this t…
math.CO2009
On Reichenbach's causal betweenness
Vasek Chvatal, Baoyindureng Wu
We characterize, by easily verifiable properties, abstract ternary relations isomorphic to the causal betweenness introduced by Hans Reichenbach.