Python Program to find the sum of a Series 1/1! + 2/2! + 3/3! + 4/4! +…….+ n/n!

In this article, we will learn about the solution and approach to solve the given problem statement.

Problem statement −Given an integer input n, we need to find the sum of a Series 1/1! + 2/2! + 3/3! + 4/4! +…….+ n/n!

Here we are implementing for loop, therefore, we get O(n) as the time complexity.

Here to reach the efficiency we calculate factorial within the same loop.

Here we frame a sumofseries function as described below −

Example

 Live Demo

def sumOfSeries(num):
   res = 0
   fact = 1
   for i in range(1, num+1):
      fact *= i
      res = res + (i/ fact)
   return res
n = 100
print("Sum: ", sumOfSeries(n))

Output

Sum: 2.7182818284590455

All variables and functions are declared in global scope as shown in the figure below.

Conclusion

In this article, we learned about the approach to find whether it is possible to make a divisible by 3 numbers using all digits in an array.