| n0 < # ar, dups(ar.indicesWhere(φ, n0) + n0 '), φ(ar[n0]), ∀ ar0, φ0. ¬ dups(ar0.indicesWhere(φ0, n0)) ∨ ¬ n0 ≤ # ar0 ⊦ |
⊦ dups(nx + nx0) ↔ dups(nx) ∨ dups(nx0) ∨ (∃ n. n ∈ nx ∧ n ∈ nx0)
n0 < # ar, φ(ar[n0]), ∀ ar0, φ0. ¬ dups(ar0.indicesWhere(φ0, n0)) ∨ ¬ n0 ≤ # ar0, dups(ar.indicesWhere(φ, n0)) ∨ dups(n0 ') ∨ (∃ n. n ∈ ar.indicesWhere(φ, n0) ∧ n ∈ n0 ') ⊦
Used terms: n0 ', ar.indicesWhere(φ, n0)