'''
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'''

from fractions import Fraction
import numpy as np
np.set_printoptions(precision=20)

n = 5
arr = [[0 for _ in range(n**2)] for _ in range(n**2)]
for x in range(n):
    for y in range(n):
        idx = x * n + y
        for dx, dy in ((1, 0), (-1, 0), (0, -1), (0, 1)):
            u, v = x + dx, y + dy
            if 0 <= u < n and 0 <= v < n:
                p = u * n + v
                arr[idx][p] = 1 / 4

            
# for r in arr:
#     print(r)
array = np.identity(n**2) - np.array(arr)   
# print(np.linalg.det(array))
res = np.linalg.inv(array) @ np.ones((n**2, 1))
print(res[n**2//2][0])