Improved lower bounds for the 2-page crossing numbers of K_{m,n} and K_n via semidefinite programming

Etienne de Klerk, Dmitrii V. Pasechnik

It has been long conjectured that the crossing numbers of the complete bipartite graph K_{m,n} and of the complete graph K_n equal Z(m,n) (the value conjectured by Zarankiewicz, wh…