# Program to find the Nth number of the series 2, 10, 24, 44, 70…..

Given a number N, the task is to find the Nth (N may be up to 10^18) term of this series:

2, 10, 24, 44, 70…..

The answer can be very large so print answer under modulo 10^9+9.

Examples:

```Input: N = 2
Output: 10

Input: N = 5
Output: 70
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach:The formula for Nth term will be:

Nth term = 3*n*n – n

Below is the implementation of the above approach:

## C++

 `// CPP program to find  ` `// the Nth term of the series ` `// 2, 10, 24, 44, 70..... ` ` `  `#include ` `using` `namespace` `std; ` ` `  `#define mod 1000000009 ` ` `  `// function to return nth term of the series ` `int` `NthTerm(``long` `long` `n) ` `{ ` `    ``long` `long` `x = (3 * n * n) % mod; ` `    ``return` `(x - n + mod) % mod; ` `} ` ` `  `// Driver code ` `int` `main() ` `{ ` ` `  `// Get N ` `    ``long` `long` `N = 4; ` ` `  `    ``// Get Nth term ` `    ``cout << NthTerm(N); ` ` `  `    ``return` `0; ` `} `

## Java

 `// Java program to find N-th ` `// term of the series: ` ` `  `import` `java.util.*; ` `import` `java.lang.*; ` `import` `java.io.*; ` ` `  `class` `GFG { ` ` `  `    ``// function to return nth term of the series ` `    ``static` `long` `NthTerm(``long` `n) ` `    ``{ ` `        ``long` `x = (``3` `* n * n) % ``1000000009``; ` `        ``return` `(x - n + ``1000000009``) % ``1000000009``; ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `main(String args[]) ` `    ``{ ` ` `  `        ``// Taking  n as 4 ` `        ``long` `N = ``4``; ` ` `  `        ``// Printing the nth term ` `        ``System.out.println(NthTerm(N)); ` `    ``} ` `} `

## Python3

 `# Python 3 program to find    ` `# N-th term of the series:    ` `     `  `   `  `# Function for calculating    ` `# Nth term of series    ` `def` `NthTerm(N) :    ` `     `  `    ``# return nth term  ` `    ``x ``=` `(``3` `*` `N``*``N)``%` `1000000009` `    ``return` `((x ``-` `N ``+` `1000000009``)``%` `1000000009``)    ` `     `  `# Driver code    ` `if` `__name__ ``=``=` `"__main__"` `:    ` `         `  `    ``N ``=` `4` `     `  `    ``# Function Calling    ` `    ``print``(NthTerm(N))  `

## C#

 `// C# program to find N-th ` `// term of the series: ` `using` `System; ` `class` `GFG ` `{ ` ` `  `// function to return nth  ` `// term of the series ` `static` `long` `NthTerm(``long` `n) ` `{ ` `    ``long` `x = (3 * n * n) % 1000000009; ` `    ``return` `(x - n + 1000000009) % 1000000009; ` `} ` ` `  `// Driver Code ` `public` `static` `void` `Main() ` `{ ` ` `  `    ``// Taking n as 4 ` `    ``long` `N = 4; ` ` `  `    ``// Printing the nth term ` `    ``Console.Write(NthTerm(N)); ` `} ` `} ` ` `  `// This code is contributed ` `// by ChitraNayal `

## PHP

 ` `

Output:

```44
```

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