C#: Get the nth tetrahedral number from a given integer(n) value

C# Sharp Math: Exercise-21 with Solution

Write a C# Sharp program to get the nth tetrahedral number from a given integer(n) value.

A tetrahedral number, or triangular pyramidal number, is a figurate number that represents a pyramid with a triangular base and three sides, called a tetrahedron. The formula for the nth tetrahedral number is represented by the 3rd rising factorial of n divided by the factorial of 3:

Sample Solution:

C# Sharp Code:

using System;
using System.Linq;
namespace exercises
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = 1;
            Console.WriteLine("\nOriginal Number:" + n);
            Console.WriteLine("Tetrahedral number:" + test(n));
            n = 2;
            Console.WriteLine("\nOriginal Number:" + n);
            Console.WriteLine("Tetrahedral number:" + test(n));
            n = 6;
            Console.WriteLine("\nOriginal Number:" + n);
            Console.WriteLine("Tetrahedral number:" + test(n));
        }
        public static int test(int n)
        {
            return n * (n + 1) * (n + 2) / 6;
        }
    }
}

Sample Output:

Original Number:1
Tetrahedral number:1

Original Number:2
Tetrahedral number:4

Original Number:6
Tetrahedral number:56

Flowchart:

C# Sharp Code Editor:

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