The following numbers form the concentric hexagonal sequence : *0, 1, 6, 13, 24, 37, 54, 73, 96, 121, 150 ……*

The number sequence forms a pattern with concentric hexagons, and the numbers denote the number of points required after the n-th stage of the pattern.

**Examples:**

Input :N = 3Output :13

Input :N = 4Output :24

**Approach :**

The above series can be referred from Concentric Hexagonal Numbers.**N**th term of the series is **3*n ^{2}/2 **

Below is the implementation of the above approach :

## C++

`// CPP program to find nth concentric hexagon number` `#include <bits/stdc++.h>` `using` `namespace` `std;` `// Function to find nth concentric hexagon number` `int` `concentric_Hexagon(` `int` `n)` `{` ` ` `return` `3 * ` `pow` `(n, 2) / 2;` `}` `// Driver code` `int` `main()` `{` ` ` `int` `n = 3;` ` ` `// Function call` ` ` `cout << concentric_Hexagon(n);` ` ` `return` `0;` `}` |

## Java

`// Java program to find` `// nth concentric hexagon number` `class` `GFG` `{` ` ` ` ` `// Function to find` ` ` `// nth concentric hexagon number` ` ` `static` `int` `concentric_Haxagon(` `int` `n)` ` ` `{` ` ` `return` `3` `* (` `int` `)Math.pow(n, ` `2` `) / ` `2` `;` ` ` `}` ` ` ` ` `// Driver Code` ` ` `public` `static` `void` `main (String[] args)` ` ` `{` ` ` `int` `n = ` `3` `;` ` ` ` ` `// Function call` ` ` `System.out.println(concentric_Haxagon(n));` ` ` `}` `}` `// This code is contributed by` `// sanjeev2552` |

## Python3

`# Python3 program to find` `# nth concentric hexagon number` ` ` `# Function to find` `# nth concentric hexagon number` `def` `concentric_Hexagon(n):` ` ` `return` `3` `*` `pow` `(n, ` `2` `) ` `/` `/` `2` `# Driver code` `n ` `=` `3` `# Function call` `print` `(concentric_Hexagon(n))` ` ` `# This code is contributed by Mohit Kumar` |

## C#

`// C# program to find nth concentric hexagon number` `using` `System;` `class` `GFG` `{` `// Function to find nth concentric hexagon number` `static` `int` `concentric_Hexagon(` `int` `n)` `{` ` ` `return` `3 * (` `int` `)Math.Pow(n, 2) / 2;` `}` `// Driver code` `public` `static` `void` `Main()` `{` ` ` `int` `n = 3;` ` ` `// Function call` ` ` `Console.WriteLine(concentric_Hexagon(n));` `}` `}` `// This code is contributed by Nidhi` |

## Javascript

`<script>` `// Javascript program to find` `// nth concentric hexagon number` `// Function to find` `// nth concentric hexagon number` `function` `concentric_Haxagon(n)` `{` ` ` `return` `parseInt(3 * Math.pow(n, 2) / 2);` `}` `// Driver code` `var` `n = 3;` ` ` `// Function call` `document.write(concentric_Haxagon(n));` ` ` `// This code is contributed by Ankita saini` `</script>` |

**Output:**

13

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