Efficient Program to Compute Sum of Series 1/1! + 1/2! + 1/3! + 1/4! + .. + 1/n!

# Python3 program to compute sum of series

# 1/1! + 1/2! + .. + 1/n!

 

# Function to find factorial of a number

def factorial(n):

    res = 1

    for i in range(2, n + 1):

            res *= i

    return res

         

# A Simple Function to return value

# of 1/1! + 1/2! + .. + 1/n!

def sum(n):

    s = 0.0

     

    for i in range(1, n + 1):

        s += 1.0 / factorial(i)

    print(s)

 

# Driver program to test above functions

n = 5

sum(n)

 

# This code is contributed by ujjwal matoiya

Output: 

1.71667