Given a number n, find the nth Centered Nonadecagonal number.

A Centered Nonadecagonal Number represents a dot in the centre and other dots surrounding it in successive nonadecagon(19 sided polygon) layers.

The first few Centered Nonadecagonal numbers are:
1, 20, 58, 115, 191, 286, 400, 533, 685, 856, 1046, 1255……………………………

Examples :

```Input :  3
Output : 58

Input : 13
Output :1483
```

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

In mathematics, Centered nonadecagonal number for n-th term is given by :

```
```

Below is the basic implementation of the above idea:

C++

 `// C++ Program to find ` `// nth centered ` `// nonadecagonal number ` `#include ` `using` `namespace` `std; ` ` `  `// centered nonadecagonal ` `//  function ` `int` `center_nonadecagon_num( ``long` `int` `n ) ` `{ ` `    ``// Formula to calculate nth ` `    ``// centered nonadecagonal number ` `    ``return` `(19 * n * n - 19 * n + 2) / 2; ` `} ` ` `  `// Driver Code ` `int` `main() ` `{ ` `    ``long` `int` `n = 2; ` `    ``cout << n << ``"th centered nonadecagonal number : "`  `                   ``<< center_nonadecagon_num(n); ` `    ``cout << endl; ` `    ``n = 7; ` `    ``cout << n << ``"th centered nonadecagonal number : "` `                  ``<< center_nonadecagon_num(n); ` ` `  `    ``return` `0; ` `} `

Java

 `// Java Program to find nth centered ` `// nonadecagonal number ` `import` `java.io.*; ` ` `  `class` `GFG { ` `     `  `    ``// centered nonadecagonal ` `    ``// function ` `    ``static` `int` `center_nonadecagon_num(``int` `n) ` `    ``{ ` `        ``// Formula to calculate nth ` `        ``// centered nonadecagonal number ` `        ``return` `(``19` `* n * n - ``19` `* n + ``2``) / ``2``; ` `    ``} ` `     `  `    ``// Driver code ` `    ``public` `static` `void` `main (String[] args) ` `    ``{ ` `        ``int` `n = ``2``; ` `        ``System.out.print ( n + ``"th centered "` `                ``+ ``"nonadecagonal number : "``); ` `        ``System.out.println (  ` `                   ``center_nonadecagon_num(n)); ` `     `  `        ``n = ``7``; ` `        ``System.out.print ( n + ``"th centered "` `                ``+ ``"nonadecagonal number : "``); ` `        ``System.out.println( ` `                  ``center_nonadecagon_num(n)); ` `    ``} ` `} ` ` `  `// This code is contributed by m_kit `

Python3

 `# Program to find nth ` `# centered nonadecagonal number ` `def` `center_nonadecagon_num(n) : ` `     `  `    ``# Formula to calculate  ` `    ``# nth centered nonadecagonal  ` `    ``# number & return it into  ` `    ``# main function. ` `     `  `    ``return` `(``19` `*` `n ``*` `n ``-`  `            ``19` `*` `n ``+` `2``) ``/``/` `2` ` `  `# Driver Code ` `if` `__name__ ``=``=` `'__main__'` `: ` `         `  `    ``n ``=` `2` `    ``print``(n,``"nd centered nonadecagonal "` `+`  `                              ``"number : "``,  ` `                ``center_nonadecagon_num(n)) ` ` `  `    ``n ``=` `7` `    ``print``(n,``"nd centered nonadecagonal "` `+`  `                              ``"number : "``,  ` `                ``center_nonadecagon_num(n)) ` ` `  `# This code is contributed by ajit `

C#

 `// C# Program to find  ` `// nth centered  ` `// nonadecagonal number ` `using` `System; ` ` `  `class` `GFG ` `{ ` `     `  `    ``// centered nonadecagonal ` `    ``// function ` `    ``static` `int` `center_nonadecagon_num(``int` `n) ` `    ``{ ` `        ``// Formula to calculate nth ` `        ``// centered nonadecagonal number ` `        ``return` `(19 * n * n -  ` `                ``19 * n + 2) / 2; ` `    ``} ` `     `  `    ``// Driver code ` `    ``static` `public` `void` `Main () ` `    ``{ ` `         `  `        ``int` `n = 2; ` `        ``Console.Write ( n + ``"th centered "` `+  ` `                 ``"nonadecagonal number : "``); ` `        ``Console.WriteLine( ` `                 ``center_nonadecagon_num(n)); ` `     `  `        ``n = 7; ` `        ``Console.Write( n + ``"th centered "` `+  ` `                ``"nonadecagonal number : "``); ` `        ``Console.WriteLine( ` `                ``center_nonadecagon_num(n)); ` `    ``} ` `} ` ` `  `// This code is contributed by ajit `

PHP

 ` `

Output :

```2th centered nonadecagonal number : 20
7th centered nonadecagonal numbe : 400
```

References:
http://oeis.org/A069132

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