SP9387 MAIN113 - Special String

A string of letters X, Y, Z is special if there are three consecutive letters from which one is X, one is Y, and one is Z. For example, XYZXYZ is special, while XXYYZ is not. Your task is to calculate how many such strings of length n are not special. ### Input First line contains an integer T(1

N/A

For each test case print total number of strings which have a length N and are not special.