i ≤ j, 0 ≤ i, 0 ≤ j ⊦ getarray(r, 0, i, addarray(r, val, j, st)) = mklist(val, i→n(i))
[[CONCRETESIMPRULES : ([CSIMPFORWARD : ⊦ i ≤ j ∧ 0 ≤ i → 0 ≤ j])]]