Given a number N, the task is to find Nth Pentacontagon number.
A Pentacontagon number is class of figurate number. It has 50 – sided polygon called pentacontagon. The N-th pentacontagon number count’s the 50 number of dots and all others dots are surrounding with a common sharing corner and make a pattern. The first few pentacontagonol numbers are 1, 50, 147, 292 …
Examples:
Input: N = 2
Output: 50
Explanation:
The second pentacontagonol number is 50.
Input: N = 3
Output: 147
Approach: The N-th pentacontagon number is given by the formula:
- Nth term of s sided polygon =
- Therefore Nth term of 50 sided polygon is
Below is the implementation of the above approach:
// C++ program for above approach #include <bits/stdc++.h> using namespace std;
// Finding the nth pentacontagon Number int pentacontagonNum( int n)
{ return (48 * n * n - 46 * n) / 2;
} // Driver Code int main()
{ int n = 3;
cout << "3rd pentacontagon Number is = "
<< pentacontagonNum(n);
return 0;
} // This code is contributed by Akanksha_Rai |
// C program for above approach #include <stdio.h> #include <stdlib.h> // Finding the nth pentacontagon Number int pentacontagonNum( int n)
{ return (48 * n * n - 46 * n) / 2;
} // Driver program to test above function int main()
{ int n = 3;
printf ( "3rd pentacontagon Number is = %d" ,
pentacontagonNum(n));
return 0;
} |
// Java program for above approach import java.util.*;
class GFG {
// Finding the nth pentacontagon number static int pentacontagonNum( int n)
{ return ( 48 * n * n - 46 * n) / 2 ;
} // Driver code public static void main(String[] args)
{ int n = 3 ;
System.out.println( "3rd pentacontagon Number is = " +
pentacontagonNum(n));
} } // This code is contributed by offbeat |
# Python3 program for above approach # Finding the nth pentacontagon Number def pentacontagonNum(n):
return ( 48 * n * n - 46 * n) / / 2
# Driver Code n = 3
print ( "3rd pentacontagon Number is = " ,
pentacontagonNum(n))
# This code is contributed by divyamohan123 |
// C# program for above approach using System;
class GFG {
// Finding the nth pentacontagon number static int pentacontagonNum( int n)
{ return (48 * n * n - 46 * n) / 2;
} // Driver code public static void Main( string [] args)
{ int n = 3;
Console.Write( "3rd pentacontagon Number is = " +
pentacontagonNum(n));
} } // This code is contributed by rutvik_56 |
<script> // javascript program for above approach // Finding the nth pentacontagon Number function pentacontagonNum( n)
{ return (48 * n * n - 46 * n) / 2;
} // Driver code let n = 3; document.write( "3rd pentacontagon Number is " + pentacontagonNum(n));
// This code contributed by gauravrajput1 </script> |
Output:
3rd pentacontagon Number is = 147
Time Complexity: O(1)
Auxiliary Space: O(1)
Reference: https://en.wikipedia.org/wiki/Pentacontagon