1!+2!+3!+..n用Python
时间: 2023-12-01 07:43:47 浏览: 34
以下是两种Python计算1!+2!+3!+...+n!的方法:
1.使用for循环计算阶乘和
```python
n = int(input("请输入一个正整数:"))
sum = 0
for i in range(1, n+1):
factorial = 1
for j in range(1, i+1):
factorial *= j
sum += factorial
print("1!+2!+3!+...+n!的和为:", sum)
```
2.使用递归函数调用阶乘方法求和
```python
def jie(n):
if n == 1:
return 1
else:
return n*jie(n-1)
n = int(input("请输入一个正整数:"))
sum = 0
if n < 1 or n > 40:
print("请重新输入数据")
else:
for i in range(1, n+1):
sum += jie(i)
print("1!+2!+3!+...+n!的和为:", sum)
```
相关问题
python 求1!+2!+3!+...+n!
以下是两种Python求1!+2!+3!+...+n!的方法:
1.使用for循环计算阶乘和
```python
n = int(input("请输入一个正整数:"))
sum = 0
for i in range(1, n+1):
factorial = 1
for j in range(1, i+1):
factorial *= j
sum += factorial
print("1!+2!+3!+...+n!的和为:", sum)
```
2.使用递归函数调用阶乘方法求和
```python
def jie(n):
if n == 1:
return 1
else:
return n*jie(n-1)
n = int(input("请输入一个正整数:"))
sum = 0
if n < 1 or n > 40:
print("请重新输入数据")
else:
for i in range(1, n+1):
sum += jie(i)
print("1!+2!+3!+...+n!的和为:", sum)
```
Python输出1!+2!+3!+......n!
以下是Python输出1!+2!+3!+......n!的代码和解释:
```python
# 定义一个函数来计算阶乘
def factorial(n):
if n == 0:
return 1
else:
return n * factorial(n-1)
# 定义一个函数来计算1!+2!+3!+......n!
def sum_of_factorials(n):
sum = 0
for i in range(1, n+1):
sum += factorial(i)
return sum
# 调用函数并输出结果
n = 5
print("1!+2!+3!+......n!的结果为:", sum_of_factorials(n))
```
运行结果为:
```
1!+2!+3!+......n!的结果为: 153
```