| H ++ r = (∅ ++ r)[r, o] ∪ H0, P(H0) ⊦ r = null, P(H), r ∈ H, r ∈ H0, ∀ r. (r ∈ H0 ↔ r ∈ H) ∧ (r ∈ H0 → H0[r] = H[r]) |
⊦ H0 = H1 ↔ (∀ r. (r ∈ H0 ↔ r ∈ H1) ∧ (r ∈ H0 → H0[r] = H1[r]))
P(H0), ∀ r0. (r0 ∈ H ++ r ↔ r0 ∈ (∅ ++ r)[r, o] ∪ H0) ∧ (r0 ∈ H ++ r → (H ++ r)[r0] = ((∅ ++ r)[r, o] ∪ H0)[r0]) ⊦ r = null, P(H), r ∈ H0, r ∈ H, ∀ r. (r ∈ H0 ↔ r ∈ H) ∧ (r ∈ H0 → H0[r] = H[r])
Used terms: (∅ ++ r)[r, o] ∪ H0, H ++ r