Megagon number

Given a number N, the task is to find N^th Megagon number.

A Megagon number is a class of figurate numbers. It has a 1000000-sided polygon called Megagon. The N-th Megagon number count’s the 1000000 number of dots and all other dots are surrounding with a common sharing corner and make a pattern. The first few Megagonol numbers are 1, 1000000, 2999997, 5999992, 9999985, 14999976, …

Examples:

Input: N = 2 
Output: 1000000 
Explanation:
The second Megagonol number is 1000000. 
Input: N = 3 
Output: 2999997 

Approach: The N-th Megagon number is given by the formula:

• Nth term of s sided polygon = 
  
• Therefore Nth term of 1000000 sided polygon is
  

• 
  

Below is the implementation of the above approach:

C++

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

// Function to find the
// nth Megagon Number
int MegagonNum(int n)
{
    return (999998 * n * n - 999996 * n) / 2;
}

// Driver Code
int main()
{
    int n = 3;
    cout << MegagonNum(n);

    return 0;
}

Java

// Java program for the above approach
class GFG{

// Function to find the
// nth Megagon Number
static int MegagonNum(int n)
{
    return (999998 * n * n - 999996 * n) / 2;
}

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

    System.out.print(MegagonNum(n));
}
}

// This code is contributed by shubham

Python3

# Python3 implementation for the
# above approach

# Function to find the
# nth Megagon Number
def MegagonNum(n):

    return (999998 * n * n - 999996 * n) // 2;

# Driver Code
n = 3;
print(MegagonNum(n));

# This code is contributed by Code_Mech

C#

// C# program for the above approach
using System;
class GFG{

// Function to find the
// nth Megagon Number
static int MegagonNum(int n)
{
    return (999998 * n * n - 999996 * n) / 2;
}

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

    Console.Write(MegagonNum(n));
}
}

// This code is contributed by sapnasingh4991

Javascript

<script>

// Javascript implementation for the
// above approach

// Function to find the
// nth Megagon Number
function MegagonNum(n)
{
    return (999998 * n * n - 999996 * n) / 2;
}

// Driver Code
var n = 3;
document.write(MegagonNum(n));


</script>

Output:

2999997

Reference: https://en.wikipedia.org/wiki/Megagon