| ∀ r. r ∈ rs → g(r) ≠ a ⊦ r = null, owns-one(a, r, rs ++ r, g(r; a)), r ∈ rs |
⊦ owns-one(a, r, rs, g) ↔ r ≠ null ∧ r ∈ rs ∧ g(r) = a ∧ (∀ r0. r0 ∈ rs ∧ r0 ≠ r → g(r0) ≠ a)
∀ r. r ∈ rs → g(r) ≠ a ⊦ r = null, r ∈ rs, r ≠ null ∧ r ∈ rs ++ r ∧ g(r; a)(r) = a ∧ (∀ r0. r0 ∈ rs ++ r ∧ r0 ≠ r → g(r; a)(r0) ≠ a)
Used terms: g(r; a), rs ++ r, r, a