--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+include "ground_2/xoa/ex_3_2.ma".
+include "ground_2/steps/rtc_max.ma".
+include "ground_2/steps/rtc_isrt.ma".
+
+(* RT-TRANSITION COUNTER ****************************************************)
+
+(* Properties with test for constrained rt-transition counter ***************)
+
+lemma isrt_max: โn1,n2,c1,c2. ๐๐โชn1,c1โซ โ ๐๐โชn2,c2โซ โ ๐๐โชn1โจn2,c1โจc2โซ.
+#n1 #n2 #c1 #c2 * #ri1 #rs1 #H1 * #ri2 #rs2 #H2 destruct
+/2 width=3 by ex1_2_intro/
+qed.
+
+lemma isrt_max_O1: โn,c1,c2. ๐๐โช0,c1โซ โ ๐๐โชn,c2โซ โ ๐๐โชn,c1โจc2โซ.
+/2 width=1 by isrt_max/ qed.
+
+lemma isrt_max_O2: โn,c1,c2. ๐๐โชn,c1โซ โ ๐๐โช0,c2โซ โ ๐๐โชn,c1โจc2โซ.
+#n #c1 #c2 #H1 #H2 >(max_O2 n) /2 width=1 by isrt_max/
+qed.
+
+lemma isrt_max_idem1: โn,c1,c2. ๐๐โชn,c1โซ โ ๐๐โชn,c2โซ โ ๐๐โชn,c1โจc2โซ.
+#n #c1 #c2 #H1 #H2 >(idempotent_max n) /2 width=1 by isrt_max/
+qed.
+
+(* Inversion properties with test for constrained rt-transition counter *****)
+
+lemma isrt_inv_max: โn,c1,c2. ๐๐โชn,c1 โจ c2โซ โ
+ โโn1,n2. ๐๐โชn1,c1โซ & ๐๐โชn2,c2โซ & (n1 โจ n2) = n.
+#n #c1 #c2 * #ri #rs #H
+elim (max_inv_dx โฆ H) -H #ri1 #rs1 #ti1 #ts1 #ri2 #rs2 #ti2 #ts2 #_ #_ #H1 #H2 #H3 #H4
+elim (max_inv_O3 โฆ H1) -H1 /3 width=5 by ex3_2_intro, ex1_2_intro/
+qed-.
+
+lemma isrt_O_inv_max: โc1,c2. ๐๐โช0,c1 โจ c2โซ โ โงโง ๐๐โช0,c1โซ & ๐๐โช0,c2โซ.
+#c1 #c2 #H
+elim (isrt_inv_max โฆ H) -H #n1 #n2 #Hn1 #Hn2 #H
+elim (max_inv_O3 โฆ H) -H #H1 #H2 destruct
+/2 width=1 by conj/
+qed-.
+
+lemma isrt_inv_max_O_dx: โn,c1,c2. ๐๐โชn,c1 โจ c2โซ โ ๐๐โช0,c2โซ โ ๐๐โชn,c1โซ.
+#n #c1 #c2 #H #H2
+elim (isrt_inv_max โฆ H) -H #n1 #n2 #Hn1 #Hn2 #H destruct
+lapply (isrt_inj โฆ Hn2 H2) -c2 #H destruct //
+qed-.
+
+lemma isrt_inv_max_eq_t: โn,c1,c2. ๐๐โชn,c1 โจ c2โซ โ eq_t c1 c2 โ
+ โงโง ๐๐โชn,c1โซ & ๐๐โชn,c2โซ.
+#n #c1 #c2 #H #Hc12
+elim (isrt_inv_max โฆ H) -H #n1 #n2 #Hc1 #Hc2 #H destruct
+lapply (isrt_eq_t_trans โฆ Hc1 โฆ Hc12) -Hc12 #H
+<(isrt_inj โฆ H โฆ Hc2) -Hc2
+<idempotent_max /2 width=1 by conj/
+qed-.