| ⊦ (as ++ adr) \ dom nodes(st) = (as \ dom nodes(st)) ++ adr, adr ∈ st |
⊦ as = as0 ↔ (∀ adr. adr ∈ as ↔ adr ∈ as0)
⊦ adr ∈ st, ∀ adr0. adr0 ∈ (as ++ adr) \ dom nodes(st) ↔ adr0 ∈ (as \ dom nodes(st)) ++ adr
Used terms: (as \ dom nodes(st)) ++ adr, (as ++ adr) \ dom nodes(st)