import numpy as np


def pow_matrix_mod(x, n):
    if not n:
        return np.eye(len(x), dtype=float)
    if n % 2 == 0:
        return pow_matrix_mod(x @ x, n // 2)
    else:
        return x @ pow_matrix_mod(x @ x, (n - 1) // 2)


N = int(input())
dp = np.zeros(7, dtype=float)
dp[0] = 1.0
A = [[0] * 7 for _ in range(7)]
for i in range(6):
    A[i][i + 1] = (6 - i) / 6
    A[i + 1][i + 1] = (i + 1) / 6

A = np.array(A)
res = dp @ pow_matrix_mod(A, N)
print(res[6])