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

**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 <bits/stdc++.h> ` `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; ` `} ` |

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## 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)); ` ` ` `} ` `} ` |

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## 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)) ` |

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## 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 ` |

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## PHP

`<?php ` `// PHP program to find ` `// the Nth term of the series ` `// 2, 10, 24, 44, 70..... ` ` ` `// function to return Nth ` `// term of the series ` `function` `NthTerm(` `$n` `) ` `{ ` ` ` `$mod` `= 1000000009; ` ` ` ` ` `$x` `= (3 * ` `$n` `* ` `$n` `) % ` `$mod` `; ` ` ` `return` `(` `$x` `- ` `$n` `+ ` `$mod` `) % ` `$mod` `; ` `} ` ` ` `// Driver code ` `$N` `= 4; ` ` ` `// Get Nth term ` `echo` `NthTerm(` `$N` `); ` ` ` `// This code is contributed ` `// by Mahadev99 ` `?> ` |

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**Output:**

44

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