⊦ 0 < j → # getarray(r, i, j, st) = i→n(j)
[[CONCRETESIMPRULES : ([CSIMPSEQ : ⊦ i→n(i) = i→n(j) ↔ abs(i) = abs(j)], [CSIMPFORWARD : ⊦ n→i(m) < j → 0 < j])]]