| s0 ++ a = ∅ ++ a0 ++ b ⊦ 1 = # s0, a0 = b, a ∈ s0 |
s0 ++ a = ∅ ++ a0 ++ b ⊦ 1 = # s0, a0 = b, a ∈ s0, b ∈ ∅ ++ a0
Used simplifier rules: eq: ⊦ a ∈ s → s ++ a = s;%eq-02: ⊦ ¬ a ∈ s → (s ++ a = ∅ ++ b ↔ a = b ∧ s = ∅);%in-04: ⊦ a ∈ ∅ ++ b ↔ a = b; Used formulas: b ∈ ∅ ++ a0