proposition: Lemma inmon_Der_imp_inmon_d : ~ dans S X -> ~ dans S V1 -> ~ dans S V2 -> forall u v : Word, isGram X V1 R1 S1 -> isGram X V2 R2 S2 -> inter V1 V2 empty -> inmonoid (union X V1) u -> Derive Ru u v -> inmonoid (union X V1) v.
proof: Proof. prolog [ isGram2 isGram4 inter_union inmon_Der_imp_Der_d inmon_Der_imp_inmon_R1_d ] 15. Qed.
imports: Ensf Words more_words Rat need fonctions Relations gram gram2 gram3