lemma rex_inv_bind_void (R):
∀p,I,L1,L2,V,T. L1 ⪤[R,ⓑ[p,I]V.T] L2 → L1 ⪤[R,V] L2 ∧ L1.ⓧ ⪤[R,T] L2.ⓧ.
#R #p #I #L1 #L2 #V #T * #f #Hf #HL elim (frees_inv_bind_void … Hf) -Hf
lemma rex_inv_bind_void (R):
∀p,I,L1,L2,V,T. L1 ⪤[R,ⓑ[p,I]V.T] L2 → L1 ⪤[R,V] L2 ∧ L1.ⓧ ⪤[R,T] L2.ⓧ.
#R #p #I #L1 #L2 #V #T * #f #Hf #HL elim (frees_inv_bind_void … Hf) -Hf