Find Nth Term of the Series 1, 5, 32, 288 in C++

In this problem, we are given an integer N. Our task is to create a program to Find Nth term of series 1,5, 32, 288 ...

Let’s take an example to understand the problem,

Input

N = 4

Output

288

Explanation

4^th term − (4^4) + (3^3) + (2^2) + (1^1) = 256 + 27 + 4 + 1 = 288

Solution Approach

A simple approach to solve the problem is by using the general formula for the nth term of the series. The formula for,

Nth term = ( N^N ) + ( (N-1)^(N-1) ) + … + ( 2^2 ) + ( 1^1 )

Program to illustrate the working of our solution,

Example

 Live Demo

#include <iostream>
using namespace std;
int calcNthTerm(int N) {
   if (N <= 1)
      return 1;
   int factorial = 1;
   for (int i = 1; i < N; i++)
      factorial *= i;
   return factorial;
}
int main() {
   int N = 8;
   cout<<N<<"th term of the series is "<<calcNthTerm(N);
   return 0;
}

Output

8th term of the series is 5040