Number of cells in the Nth order figure

Given an integer N, the task is to find the number of cells in N^th order figure of the given type: 

Examples:

Input: N = 2 
Output: 5
Input: N = 3 
Output: 13 

Approach: It can be observed that for the values of N = 1, 2, 3, … a series will be formed as 1, 5, 13, 25, 41, 61, 85, 113, 145, 181, … whose N^th term will be N² + (N – 1)².
Below is the implementation of the above approach: 

C++

// C++ implementation of the approach
#include <bits/stdc++.h>
using namespace std;

// Function to return the number
// of cells in the nth order
// figure of the given type
int cntCells(int n)
{
    int cells = pow(n, 2) + pow(n - 1, 2);
    return cells;
}

// Driver code
int main()
{
    int n = 3;

    cout << cntCells(n);

    return 0;
}

Java

// Java implementation of the approach
class GFG
{

// Function to return the number
// of cells in the nth order
// figure of the given type
static int cntCells(int n)
{
    int cells = (int)Math.pow(n, 2) +
                (int)Math.pow(n - 1, 2);
    return cells;
}

// Driver code
public static void main(String[] args)
{
    int n = 3;

    System.out.println(cntCells(n));
}
}

// This code is contributed by Code_Mech

Python3

# Python3 implementation of the approach

# Function to return the number
# of cells in the nth order
# figure of the given type
def cntCells(n) :

    cells = pow(n, 2) + pow(n - 1, 2);

    return cells;

# Driver code
if __name__ == "__main__" :

    n = 3;

    print(cntCells(n));

# This code is contributed by AnkitRai01

C#

// C# implementation of the approach
using System;

class GFG
{

// Function to return the number
// of cells in the nth order
// figure of the given type
static int cntCells(int n)
{
    int cells = (int)Math.Pow(n, 2) +
                (int)Math.Pow(n - 1, 2);
    return cells;
}

// Driver code
public static void Main(String[] args)
{
    int n = 3;

    Console.WriteLine(cntCells(n));
}
}

// This code is contributed by 29AjayKumar

Javascript

<script>

// Javascript implementation of the approach

// Function to return the number
// of cells in the nth order
// figure of the given type
function cntCells(n)
{
    var cells = Math.pow(n, 2) + Math.pow(n - 1, 2);
    return cells;
}

// Driver code
var n = 3;
document.write(cntCells(n));


</script>

Output:

13

Time Complexity: O(1)
Auxiliary Space: O(1), as no extra space is required