| ∀ a. rmdup(x0 -l a) = rmdup(x0) -l a ⊦ rmdup(x0 -l a0) = rmdup(a0 ' + x0) -l a0 |
⊦ rmdup(a ' + x) = (a ∈ x ⊃ rmdup(x);a ' + rmdup(x))
∀ a. rmdup(x0 -l a) = rmdup(x0) -l a ⊦ rmdup(x0 -l a0) = (a0 ∈ x0 ⊃ rmdup(x0);a0 ' + rmdup(x0)) -l a0
Used terms: x0, a0