# Find the Nth term of the series 2 + 6 + 13 + 23 + . . .

Given an integer **N**. The task is to write a program to find the **Nth** term of the given series:

2 + 6 + 13 + 23 + …

**Examples**:

Input : N = 5 Output : 36 Input : N = 10 Output : 146

Refer the article on How to find Nth term of series to know idea behind finding Nth term of any given series.

The generalized **N-th** term of given series is:

Below is the implementation of above approach:

## C++

`//CPP program to find Nth term of the series` `// 2 + 6 + 13 + 23 + 36 + ...` `#include<bits/stdc++.h>` `using` `namespace` `std;` `// calculate Nth term of given series` `int` `Nth_Term(` `int` `n)` `{` ` ` `return` `(3 * ` `pow` `(n, 2) - n + 2) / (2);` `}` `// Driver code` `int` `main()` `{` `int` `N = 5;` `cout<<Nth_Term(N)<<endl;` `}` |

## Java

`//Java program to find Nth term of the series` `// 2 + 6 + 13 + 23 + 36 + ...` `import` `java.io.*;` `class` `GFG {` `// calculate Nth term of given series` `static` `int` `Nth_Term(` `int` `n)` `{` ` ` `return` `(` `int` `)(` `3` `* Math.pow(n, ` `2` `) - n + ` `2` `) / (` `2` `);` `}` `// Driver code` ` ` `public` `static` `void` `main (String[] args) {` ` ` `int` `N = ` `5` `;` ` ` `System.out.println(Nth_Term(N));` ` ` `}` `}` `// This code is contributed by anuj_67..` |

## Python3

`# Python program to find Nth term of the series` `# 2 + 6 + 13 + 23 + 36 + ...` `# calculate Nth term of given series` `def` `Nth_Term(n):` ` ` `return` `(` `3` `*` `pow` `(n, ` `2` `) ` `-` `n ` `+` `2` `) ` `/` `/` `(` `2` `)` `# Driver code` `N ` `=` `5` `print` `(Nth_Term(N))` |

## C#

`// C# program to find Nth term of the series` `// 2 + 6 + 13 + 23 + 36 + ...` `class` `GFG` `{` `// calculate Nth term of given series` `static` `int` `Nth_Term(` `int` `n)` `{` ` ` ` ` `return` `(` `int` `)(3 * System.Math.Pow(n, 2) -` ` ` `n + 2) / (2);` `}` `// Driver code` `static` `void` `Main ()` `{` ` ` `int` `N = 5;` ` ` `System.Console.WriteLine(Nth_Term(N));` `}` `}` `// This code is contributed by mits` |

## PHP

`<?php` `// PHP program to find` `// Nth term of the series` `// 2 + 6 + 13 + 23 + 36 + ...` `// calculate Nth term of given series` `function` `Nth_Term(` `$n` `)` `{` ` ` `return` `(3 * pow(` `$n` `, 2) - ` `$n` `+ 2) / (2);` `}` `// Driver code` `$N` `= 5;` `echo` `(Nth_Term(` `$N` `));` `// This code is contributed` `// by Sach_Code` `?>` |

## Javascript

`<script>` `// java script program to find` `// Nth term of the series` `// 2 + 6 + 13 + 23 + 36 + ...` `// calculate Nth term of given series` `function` `Nth_Term(n)` `{` ` ` `return` `(3 * Math.pow(n, 2) - n + 2) / (2);` `}` `// Driver code` `let N = 5;` `document.write (Nth_Term(N));` `// This code is contributed` `// by bobby` `</script>` |

**Output:**

36

**Time complexity**: O(1), since there is no loop or recursion.

**Auxiliary Space: **O(1), since no extra space has been taken.