# Find Nth term of the series 2, 3, 10, 15, 26….

Given a number N, the task is to find the Nth term in series 2, 3, 10, 15, 26….

Example:

```Input: N = 2
Output: 3
2nd term = (2*2)-1
= 3

Input: N = 5
Output: 26
5th term = (5*5)+1
= 26
```

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

Approach:

• Nth number of the series is obtained by
1. Squaring the number itself.
2. If the number is odd, add 1 to the squared number. And, subtract 1 if the number is even
• Since the starting number of the series is 2

1st term = 2
2nd term = (2 * 2) – 1 = 3
3rd term = (3 * 3) + 1 = 10
4th term = (4 * 4) – 1 = 15
5th term = (5 * 5) + 1 = 26
and so on….

• In general, Nth number is obtained by formula:

Below is the implementation of the above approach:

## C++

 `// C++ program to find Nth term ` `// of the series 2, 3, 10, 15, 26.... ` ` `  `#include ` `using` `namespace` `std; ` ` `  `// Function to find Nth term ` `int` `nthTerm(``int` `N) ` `{ ` `    ``int` `nth = 0; ` ` `  `    ``// Nth term  ` `    ``if` `(N % 2 == 1) ` `        ``nth = (N * N) + 1; ` `    ``else` `        ``nth = (N * N) - 1; ` ` `  `    ``return` `nth; ` `} ` ` `  `// Driver Method ` `int` `main() ` `{ ` `    ``int` `N = 5; ` ` `  `    ``cout << nthTerm(N) << endl; ` ` `  `    ``return` `0; ` `} `

## Java

 `// Java program to find Nth term ` `// of the series 2, 3, 10, 15, 26.... ` `class` `GFG ` `{ ` ` `  `// Function to find Nth term ` `static` `int` `nthTerm(``int` `N) ` `{ ` `    ``int` `nth = ``0``; ` ` `  `    ``// Nth term  ` `    ``if` `(N % ``2` `== ``1``) ` `        ``nth = (N * N) + ``1``; ` `    ``else` `        ``nth = (N * N) - ``1``; ` ` `  `    ``return` `nth; ` `} ` ` `  `// Driver code ` `public` `static` `void` `main(String[] args) ` `{ ` `    ``int` `N = ``5``; ` ` `  `    ``System.out.print(nthTerm(N) +``"\n"``); ` ` `  `} ` `} ` ` `  `// This code is contributed by Rajput-Ji `

## Python3

 `# Python3 program to find Nth term  ` `# of the series 2, 3, 10, 15, 26....  ` ` `  `# Function to find Nth term  ` `def` `nthTerm(N) :  ` `    ``nth ``=` `0``;  ` ` `  `    ``# Nth term  ` `    ``if` `(N ``%` `2` `=``=` `1``) : ` `        ``nth ``=` `(N ``*` `N) ``+` `1``;  ` `    ``else` `: ` `        ``nth ``=` `(N ``*` `N) ``-` `1``;  ` ` `  `    ``return` `nth;  ` ` `  `# Driver Method  ` `if` `__name__ ``=``=` `"__main__"` `:  ` `    ``N ``=` `5``;  ` `    ``print``(nthTerm(N)) ;  ` ` `  `# This code is contributed by AnkitRai01 `

## C#

 `// C# program to find Nth term ` `// of the series 2, 3, 10, 15, 26.... ` `using` `System; ` ` `  `class` `GFG ` `{ ` ` `  `// Function to find Nth term ` `static` `int` `nthTerm(``int` `N) ` `{ ` `    ``int` `nth = 0; ` ` `  `    ``// Nth term  ` `    ``if` `(N % 2 == 1) ` `        ``nth = (N * N) + 1; ` `    ``else` `        ``nth = (N * N) - 1; ` ` `  `    ``return` `nth; ` `} ` ` `  `// Driver code ` `public` `static` `void` `Main(String[] args) ` `{ ` `    ``int` `N = 5; ` ` `  `    ``Console.Write(nthTerm(N) +``"\n"``); ` `} ` `} ` ` `  `// This code is contributed by PrinciRaj1992 `

Output:

```26
```

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