| rs1 ∩ rs0 = ∅, R[rs0, cf, af], o[ls(r, x)](mk(rs1, cf, af)) ⊦ r = null, r ∈ rs0, r ∈ rs1 |
⊦ o[P](mk(rs, cf, af)) ↔ P(mk(rs, cf)) ∧ (∀ r. r ∈ rs → af(r) = o)
rs1 ∩ rs0 = ∅, R[rs0, cf, af], ls(r, x)(mk(rs1, cf)), ∀ r. r ∈ rs1 → af(r) = o ⊦ r = null, r ∈ rs1, r ∈ rs0
Used terms: af, cf, rs1, ls(r, x), o