def spiral_from_center(n):
matrix = [[0 for _ in range(n)] for _ in range(n)]
x = y = n // 2
num = 1
matrix[y][x] = num
directions = [(0, 1), (1, 0), (0, -1), (-1, 0)]
step = 1
while num < n * n:
for i, (dx, dy) in enumerate(directions):
for _ in range(step):
if num >= n * n:
break
x += dx
y += dy
num += 1
if 0 <= x < n and 0 <= y < n:
matrix[x][y] = num
if i % 2 == 1:
step += 1
return matrix
n = 17
matrix = spiral_from_center(n)
for row in matrix:
print(" ".join(f"{x:3}" for x in row))
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