⊦ arraycomp(r1, i1, r2, i2, j, st) ↔ (∀ i. 0 ≤ i ∧ i < j → st[r1 -- (i1 + i) '] = st[r2 -- (i2 + i) '])
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ i < 0 ∧ 0 ≤ j → ¬ j < i])]]