--- /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/steps/rtc_isrt_shift.ma".
+include "ground/steps/rtc_isrt_max.ma".
+
+(* RT-TRANSITION COUNTER ****************************************************)
+
+(* Inversion properties with test for constrained rt-transition counter *****)
+
+lemma isrt_inv_max_shift_sn: โn,c1,c2. ๐๐โชn,โ*c1 โจ c2โซ โ
+ โงโง ๐๐โช0,c1โซ & ๐๐โชn,c2โซ.
+#n #c1 #c2 #H
+elim (isrt_inv_max โฆ H) -H #n1 #n2 #Hc1 #Hc2 #H destruct
+elim (isrt_inv_shift โฆ Hc1) -Hc1 #Hc1 * -n1
+/2 width=1 by conj/
+qed-.