| i2 ^2 + i1 ^2 + i0 ^2 + i ^2 = j0 * j, ~1 ≤ j0, ≡mod(0, i, j0), 1 < j, 0 < j, 0 < j0, prime(j), j0 < j, ≡mod(0, i2, j0), ≡mod(0, i1, j0), ≡mod(0, i0, j0), 0 ≤ j, ∀ 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) |
i2 ^2 + i1 ^2 + i0 ^2 + i ^2 = j0 * j, ≡mod(0, i, j0), ≡mod(0, i1, j0), ≡mod(0, i0, j0), ≡mod(0, i2, j0), prime(j), j0 < j, 1 < j, 0 < j, 0 < j0, 0 ≤ j, j ≠ 2, j0 ≠ 1 ⊦
Used terms: i2, i1, i0, i, j0, j