# C++ program to find n-th term of series 2, 10, 30, 68, 130 …

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In this problem, we are given an integer N. The task is to find the n-th term in series 2, 10, 30, 68, 130...

Let’s take an example to understand the problem,

## Input

N = 7

## Output

350

## Explanation

The series is 2, 10, 30, 68, 130, 222, 350...

## Solution Approach

A simple solution to the problem is by finding the general term of the series. Here, the Nth term of the series is N^3 + N. This is found by subtracting the current element with the current index.

For i,
i = 1, T(1) = 2 = 1 + 1 = 1^3 + 1
i = 2, T(1) = 10 = 8 + 2 = 2^3 + 2
i = 3, T(1) = 30 = 27 + 3 = 3^3 + 2

Program to illustrate the working of our solution,

## Example

Live Demo

#include <iostream>
using namespace std;
int findNthTerm(int N) {
return ((N*N*N) + N);
}
int main() {
int N = 8;
cout<<"The "<<N<<"th term of the series is "<<findNthTerm(N);
return 0;
}

## Output

The 8th term of the series is 520
Updated on 13-Mar-2021 12:24:30