| ⊦ (a0 ∈ st -- a ∧ ¬ a0 ∈ s ↔ a0 ∈ (st \ s) -- a) ∧ (a0 ∈ st -- a ∧ ¬ a0 ∈ s → (st -- a)[a0] = ((st \ s) -- a)[a0]) |
⊦ a ∈ st -- b ↔ a ≠ b ∧ a ∈ st
⊦ (a0 ∈ st -- a ∧ ¬ a0 ∈ s ↔ a0 ≠ a ∧ a0 ∈ st \ s) ∧ (a0 ∈ st -- a ∧ ¬ a0 ∈ s → (st -- a)[a0] = ((st \ s) -- a)[a0])
Used terms: a, st \ s, a0