⊦ ∃ i0, j0. gcd(i, j) = i * i0 + j * j0
gcd(i, j) = 1, 0 ≤ j, 0 ≤ i, ∃ i0, j0. gcd(i, j) = i * i0 + j * j0 ⊦ ∃ i0. 0 ≤ i0 ∧ j | i * i0 - 1
Used terms: i, j