Find the value of: (5 + 1) (the square of 5 + 1) (the square of 5 + 1) (the square of 5 + 1) (the octagon of 5 + 1)

Find the value of: (5 + 1) (the square of 5 + 1) (the square of 5 + 1) (the square of 5 + 1) (the octagon of 5 + 1)

(5+1)(5^2+1)(5^4+1)(5^8+1)=[(5-1)(5+1)(5^2+1)(5^4+1)(5^8+1)]÷(5-1)=[(5^2-1)(5^2+1)(5^4+1)(5^8+1)]÷(5-1)=[(5^4-1)(5^4+1)(5^8+1)]÷4=[(5^8-1)(5^8+1)]÷4=(5^16-1)/4