| rmdup(z) = y + a ' + z0, a ∈ z, ∀ y. (∀ a. a ∈ x0 ↔ a ∈ y) → # rmdup(x0) = # rmdup(y), ∀ a0. a0 ≠ a → (a0 ∈ x0 ↔ a0 ∈ y0 ∨ a0 ∈ z) ⊦ # rmdup(x0) + 1 = # rmdup(y0 + z), a ∈ y0, a ∈ x0, a ∈ y, a ∈ z0 |
⊦ rmdup(x + rmdup(y)) = rmdup(x + y)
rmdup(z) = y + a ' + z0, a ∈ z, ∀ y. (∀ a. a ∈ x0 ↔ a ∈ y) → # rmdup(x0) = # rmdup(y), ∀ a0. a0 ≠ a → (a0 ∈ x0 ↔ a0 ∈ y0 ∨ a0 ∈ z) ⊦ # rmdup(x0) + 1 = # rmdup(y0 + rmdup(z)), a ∈ y0, a ∈ x0, a ∈ y, a ∈ z0
Used terms: z, y0