-fact minuss_inv_cons1_aux: ∀des1,des2,i. des1 ▭ i ≡ des2 →
- ∀l,m,des. des1 = {l, m} @ des →
- l ≤ i ∧ des ▭ m + i ≡ des2 ∨
- ∃∃des0. i < l & des ▭ i ≡ des0 &
- des2 = {l - i, m} @ des0.
-#des1 #des2 #i * -des1 -des2 -i
-[ #i #l #m #des #H destruct
-| #des1 #des #l1 #m1 #i1 #Hil1 #Hcs #l2 #m2 #des2 #H destruct /3 width=3 by ex3_intro, or_intror/
-| #des1 #des #l1 #m1 #i1 #Hli1 #Hcs #l2 #m2 #des2 #H destruct /3 width=1 by or_introl, conj/
+fact minuss_inv_cons1_aux: ∀cs1,cs2,i. cs1 ▭ i ≡ cs2 →
+ ∀l,m,cs. cs1 = {l, m} @ cs →
+ l ≤ i ∧ cs ▭ m + i ≡ cs2 ∨
+ ∃∃cs0. i < l & cs ▭ i ≡ cs0 &
+ cs2 = {l - i, m} @ cs0.
+#cs1 #cs2 #i * -cs1 -cs2 -i
+[ #i #l #m #cs #H destruct
+| #cs1 #cs #l1 #m1 #i1 #Hil1 #Hcs #l2 #m2 #cs2 #H destruct /3 width=3 by ex3_intro, or_intror/
+| #cs1 #cs #l1 #m1 #i1 #Hli1 #Hcs #l2 #m2 #cs2 #H destruct /3 width=1 by or_introl, conj/