src/ZF/Trancl.thy
changeset 13784 b9f6154427a4
parent 13534 ca6debb89d77
child 14653 0848ab6fe5fc
equal deleted inserted replaced
13783:3294f727e20d 13784:b9f6154427a4
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   164 
   165 (*transitivity of transitive closure!! -- by induction.*)
   165 (*transitivity of transitive closure!! -- by induction.*)
   166 lemma trans_rtrancl: "trans(r^*)"
   166 lemma trans_rtrancl: "trans(r^*)"
   167 apply (unfold trans_def)
   167 apply (unfold trans_def)
   168 apply (intro allI impI)
   168 apply (intro allI impI)
   169 apply (erule_tac b = "z" in rtrancl_induct, assumption)
   169 apply (erule_tac b = z in rtrancl_induct, assumption)
   170 apply (blast intro: rtrancl_into_rtrancl) 
   170 apply (blast intro: rtrancl_into_rtrancl) 
   171 done
   171 done
   172 
   172 
   173 lemmas rtrancl_trans = trans_rtrancl [THEN transD, standard]
   173 lemmas rtrancl_trans = trans_rtrancl [THEN transD, standard]
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   174