| ⊦ (∃ key. key ∈ ks ∧ key ∈ ri ∧ adr = ri[key]) ∨ adr ∈ ri \ ks ↔ adr ∈ ri |
⊦ adr ∈ ri ↔ (∃ key. key ∈ ri ∧ ri[key] = adr)
⊦ (∃ key. key ∈ ks ∧ key ∈ ri ∧ adr = ri[key]) ∨ (∃ key. key ∈ ri \ ks ∧ (ri \ ks)[key] = adr) ↔ adr ∈ ri
Used terms: ri \ ks, adr