4ₓ3⁶ + 7ₓ3⁷ = 3⁶(4 + 7ₓ3) = 3⁶ₓ25 = 3⁶ₓ5² = (3³ₓ5)²
4ₓ5²⁰ + 9ₓ5²¹ = 5²⁰(4 + 9ₓ5) = 5²⁰ₓ49 = 5²⁰ₓ7² = (5¹⁰ₓ7)²
2¹⁰ + 3ₓ2¹⁰ + 5ₓ4⁵ = 2¹⁰ + 3ₓ2¹⁰ + 5ₓ2¹⁰ = 2¹⁰(1 + 3 + 5) = 2¹⁰ₓ3² = (2⁵ₓ3)²
