杨辉三角
import numpy as np

n = int(input('请输入一个整数：'))
z = np.zeros((n,n), dtype = 'i')

z[0][0] = 1

for i in range(1, n):
z[i][0] = 1
z[i][i] = 1
for j in range(1, i):
z[i][j] = z[i-1][j-1] + z[i-1][j]


for i in range(n):
for j in range(i+1):
print('{:4s}'.format(str(z[i][j])), end = '')
print()