| ∃ i3, i4, i5, i6. ≡mod(i3, i, j0) ∧ abs(i3) ≤ j0 / 2 ∧ ≡mod(i4, i0, j0) ∧ abs(i4) ≤ j0 / 2 ∧ ≡mod(i5, i1, j0) ∧ abs(i5) ≤ j0 / 2 ∧ ≡mod(i6, i2, j0) ∧ abs(i6) ≤ j0 / 2, i2 ^2 + i1 ^2 + i0 ^2 + i ^2 = j0 * j, j0 < j, prime(j), 0 < j0, 0 < j, 1 < j, ∀ i3, i4, i5, i6, j1. 0 < j1 ∧ j1 < j0 → i3 ^2 + i4 ^2 + i5 ^2 + i6 ^2 ≠ j1 * j ⊦ even(j0), j0 = 1, j = 2 |
i2 ^2 + i1 ^2 + i0 ^2 + i ^2 = j0 * j, 1 < j, 0 < j, 0 < j0, prime(j), j0 < j, abs(i3) ≤ j0 / 2, ≡mod(i3, i2, j0), abs(i4) ≤ j0 / 2, ≡mod(i4, i1, j0), abs(i5) ≤ j0 / 2, ≡mod(i5, i0, j0), abs(i6) ≤ j0 / 2, ≡mod(i6, i, j0), ∀ i3, i4, i5, i6, j1. 0 < j1 ∧ j1 < j0 → i3 ^2 + i4 ^2 + i5 ^2 + i6 ^2 ≠ j1 * j ⊦ j = 2, j0 = 1, even(j0)