If the first n terms of the equal ratio sequence {an} and Sn = T5 ^ (n-2) are known, then the value of the real number T is

If the first n terms of the equal ratio sequence {an} and Sn = T5 ^ (n-2) are known, then the value of the real number T is

Should be Sn = T5 ^ n-2?
If so, t = 2