Icosahedral Number

Given a number n, find the n-th icosahedral number. The Icosahedral Number is class of figurative number that represents an icosahedron(a polyhedron with 20 faces) Source : Wiki).

The first few Icosahedral Numbers are 1, 12, 48, 124, 255, 456, 742, 1128, 1629…………..

Examples :

Input : 5
Output :255

Input :10
Output :2260

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

n-th term of Icosahedral Number is given by: Basic implementation of the above idea:

C++

 // Icosahedral number to find // n-th term in C++ #include using namespace std;    // Function to find // Icosahedral number int icosahedralnum(int n) {     // Formula to calculate nth     // Icosahedral number &     // return it into main function.     return (n * (5 * n * n - 5 * n + 2)) / 2; }    // Driver Code int main() {     int n = 7;        cout << icosahedralnum(n);     return 0; }

Java

 // Icosahedral number to find // n-th term in Java import java.io.*;    class GFG {            // Function to find     // Icosahedral number     static int icosahedralnum(int n)     {         // Formula to calculate nth         // Icosahedral number &         // return it into main function.                    return (n * (5 * n * n - 5 *                             n + 2)) / 2;     }        // Driver Code     public static void main (String[] args)      {         int n = 7;         System.out.println(                         icosahedralnum(n));     } }    // This code is contributed by aj_36.

Python3

 # Python 3 Program to find  # nth Icosahedral number    # Icosahedral number # number function def icosahedralnum(n) :            # Formula to calculate nth     # Icosahedral number     # return it into main function.     return (n * (5 * n * n -                   5 * n + 2)) // 2       # Driver Code if __name__ == '__main__' :                n = 7     print(icosahedralnum(n))    # This code is contributed aj_36

C#

 // Icosahedral number to  // find n-th term in C# using System;    class GFG {            // Function to find     // Icosahedral number     static int icosahedralnum(int n)     {         // Formula to calculate         // nth Icosahedral number         // & return it into main          // function.         return (n * (5 * n * n -                       5 * n + 2)) / 2;     }        // Driver Code     static public void Main ()     {         int n = 7;         Console.WriteLine(icosahedralnum(n));     } }    // This code is contributed by ajit

PHP



Output

742

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