| key-cons(ndx0) ↔ (∀ n. n < # ndx0 → key-cons(ndx0[n].key, ndx0[n])), ∀ n. ¬ # ndx0 < n → key-cons((nd ' + ndx0)[n].key, (nd ' + ndx0)[n]) ⊦ key-cons(nd.key, nd) ∧ key-cons(ndx0) |
∀ n. ¬ # ndx0 < n → key-cons((nd ' + ndx0)[n].key, (nd ' + ndx0)[n]) ⊦ key-cons(ndx0), ∀ n. n < # ndx0 → key-cons(ndx0[n].key, ndx0[n]), key-cons(nd.key, nd) ∧ key-cons(ndx0)
key-cons(ndx0), ∀ n. ¬ # ndx0 < n → key-cons((nd ' + ndx0)[n].key, (nd ' + ndx0)[n]), ∀ n. n < # ndx0 → key-cons(ndx0[n].key, ndx0[n]) ⊦ key-cons(nd.key, nd) ∧ key-cons(ndx0)