a.(x^18-1)(x^18+1)=(x^9-1)(x^9+1)(x^18+1)
b.(x^36-1)(x^36+1)=(x^18-1)(x^18+1)(x^36+1)=(x^9-1)(x^9+1)(x^18+1)(x^36+1)
c.(x^128-1)(x^128+1)=(x^64-1)(x^64+1)(x^128+1)=(x^9-1)(x^9+1)(x^18+1)(x^36+1)(x^64+1)(x^128+1)
d.(x^512-1)(x^512+1)=(x^256-1)(x^256+1)(x^512+1)=(x^9-1)(x^9+1)(x^18+1)(x^36+1)(x^64+1)(x^128+1)(x^256+1)(x^512+1)