fact: Fixpoint Kempe_tree_closure d : ktc_fun := if d is d'.+1 then ktc_dostep2c (Kempe_tree_closure d') else fun ctu ctr gtu => (ctu, gtree_restrict gtu (GtrCons Bstack0 ctr GtrNil)).
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap geometry color chromogram coloring cfmap) fourcolor(cfcolor dyck ctree initctree gtree initgtree) fourcolor(gtreerestrict ctreerestrict)