Program to find the Nth term of the series 3, 7, 13, 21, 31…..

Given a number N, the task is to find the Nth term of this series:

3, 7, 13, 21, 31, …….

**Examples:**

Input:N = 4Output:21Explanation:Nth term = (pow(N, 2) + N + 1) = (pow(4, 2) + 4 + 1) = 21Input:N = 11Output:133

**Approach:**

Subtracting these two equations we get

Therefore, the Nth Term of the given series is:

Below is the implementation of the above approach:

## C++

`// CPP program to find the Nth term of given series.` `#include <iostream>` `#include <math.h>` `using` `namespace` `std;` `// Function to calculate sum` `long` `long` `int` `getNthTerm(` `long` `long` `int` `N)` `{` ` ` `// Return Nth term` ` ` `return` `(` `pow` `(N, 2) + N + 1);` `}` `// driver code` `int` `main()` `{` ` ` `// declaration of number of terms` ` ` `long` `long` `int` `N = 11;` ` ` `// Get the Nth term` ` ` `cout << getNthTerm(N);` ` ` `return` `0;` `}` |

## Java

`// Java code to find the Nth term of given series.` `import` `java.util.*;` `class` `solution` `{` `// Function to calculate sum` `static` `long` `getNthTerm(` `long` `N)` `{` ` ` ` ` `// Return Nth term` ` ` `return` `((` `int` `)Math.pow(N, ` `2` `) + N + ` `1` `);` `}` `//Driver program` `public` `static` `void` `main(String arr[])` `{` ` ` ` ` `// declaration of number of terms` ` ` `long` `N = ` `11` `;` ` ` `// Get the Nth term` ` ` `System.out.println(getNthTerm(N));` `}` `}` `//THis code is contibuted by` `//Surendra_Gangwar` |

## Python3

`# Python3 Code to find the` `# Nth term of given series.` `# Function to calculate sum` `def` `getNthTerm(N):` ` ` ` ` `# Return Nth term` ` ` `return` `(` `pow` `(N, ` `2` `) ` `+` `N ` `+` `1` `)` `# driver code` `if` `__name__` `=` `=` `'__main__'` `:` ` ` `# declaration of number of terms` ` ` `N ` `=` `11` ` ` `# Get the Nth term` ` ` `print` `(getNthTerm(N))` `# This code is contributed by` `# Sanjit_Prasad` |

## C#

`// C# code to find the Nth` `// term of given series.` `using` `System;` `class` `GFG` `{` `// Function to calculate sum` `static` `long` `getNthTerm(` `long` `N)` `{` ` ` `// Return Nth term` ` ` `return` `((` `int` `)Math.Pow(N, 2) + N + 1);` `}` `// Driver Code` `static` `public` `void` `Main ()` `{` ` ` ` ` `// declaration of number` ` ` `// of terms` ` ` `long` `N = 11;` ` ` `// Get the Nth term` ` ` `Console.Write(getNthTerm(N));` `}` `}` `// This code is contibuted by Raj` |

## PHP

`<?php` `// PHP program to find the ` `// Nth term of given series ` `// Function to calculate sum ` `function` `getNthTerm(` `$N` `) ` `{ ` ` ` `// Return Nth term ` ` ` `return` `(pow(` `$N` `, 2) + ` `$N` `+ 1); ` `} ` `// Driver code ` `// declaration of number of terms ` `$N` `= 11; ` `// Get the Nth term ` `echo` `getNthTerm(` `$N` `); ` `// This code is contributed by Raj` `?>` |

## Javascript

`<script>` `// JavaScript program to find the Nth term of given series. ` `// Function to calculate sum ` `function` `getNthTerm(N) ` `{ ` ` ` `// Return Nth term ` ` ` `return` `(Math.pow(N, 2) + N + 1); ` `} ` ` ` `// driver code ` ` ` `// declaration of number of terms ` ` ` `let N = 11; ` ` ` ` ` `// Get the Nth term ` ` ` `document.write(getNthTerm(N)); ` ` ` `// This code is contributed by Surbhi Tyagi` `</script>` |

**Output:**

133

**Time Complexity:** O(1)

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