proposition: Lemma size_spoke_ring : size r = arity x.
proof: Proof. by rewrite /r size_map size_rev /p /orbit size_traject. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap jordan geometry color chromogram) fourcolor(coloring patch snip sew revsnip kempe) fourcolor(ctree initctree gtree initgtree ctreerestrict) fourcolor(gtreerestrict cfmap cfcolor kempetree)