Write the first for terms a1=2 and an=an-1^(-3) if n is greater than or equal to 2
a2 = a1^(-3) = 2^(-3) = 1/8
a3 = a2^(-3) = (1/8)^(-3) = 8^3 = 512
a4 = a3^(-3) = 512^(-3) = 1/512^3 = 1/(512*512*512)
a3 = a2^(-3) = (1/8)^(-3) = 8^3 = 512
a4 = a3^(-3) = 512^(-3) = 1/512^3 = 1/(512*512*512)