程序代码：

def jiech(index):
    '''
    计算阶乘
    '''
    s = 1
    for i in range(1,index + 1):
        s = i * s
    return s


s = 0

for i in range(1,51):
    s += 1 / jiech(i)


print("%.6f" % s)

程序代码：

def fact(n):
    return 1 if n=0 or n==1 else n*fact(n-1)
s=0
for i in range(1,51):
    s+=1/fact(i)
print(round(s,6))