| ⊦ ordered(ixs, x) ∧ inv(ixs, n) ∧ n < # x → (¬ ordered(pushx(n, ixs, x), x) ↔ false) |
n < # x, inv(ixs, n), ordered(ixs, x) ⊦ x = [], ordered(pushx(n, ixs, x), x)
[Concretesimprules((Csimpnamedseq(list-data,,l, ⊦ # x = 0 ↔ x = []) Csimpnamedforward(nat-basic1,,f, ⊦ m < n → n ≠ 0)))]