fact: Record planar_plain_cubic_connected : Prop := PlanarPlainCubicConnected { planar_plain_cubic_connected_base :> plain_cubic_connected; planar_plain_cubic_connected_is_planar :> planar G }.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap jordan)