pythondp = [1, 1, 3] for i in range(3, 251): dp.append(dp[i - 1] + dp[i - 2] * 2) while True: try: N = int(input()) print(dp[N]) except: break
dp = [1, 1, 3] for i in range(3, 251): dp.append(dp[i - 1] + dp[i - 2] * 2) while True: try: N = int(input()) print(dp[N]) except: break