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math.CO2015
Levi's Lemma, pseudolinear drawings of , and empty triangles
Alan Arroyo, Dan McQuillan, Bruce Richter +1
There are three main thrusts to this article: a new proof of Levi's Enlargement Lemma for pseudoline arrangements in the real projective plane; a new characterization of pseudoline…
math.CO2013
On the crossing number of K_13
Dan McQuillan, Shengjun Pan, R. Bruce Richter
Since the crossing number of K_{12} is now known to be 150, it is well-known that simple counting arguments and Kleitman's parity theorem for the crossing number of K_{2n+1} combin…