using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ch601
{
    class Program
    {
        static void Main(string[] args)
        {
            /******begin*******/
            int n = Convert.ToInt32(Console.ReadLine());
            if (n>=1 && n<=9)
            {
                for (int j = 1; j <= n; j++)
                {
                    for (int i = 1; i <= j; i++)
                    {
                        Console.Write("{0}*{1}={2}\t", j, i ,i * j);
                    }
                    Console.WriteLine();
                }
            }
            else
            {
                Console.WriteLine("input error!");
            }
            Console.ReadKey();
            /*******end********/

        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ch602
{
    class Program
    {
        static void Main(string[] args)
        {
            /******begin*******/
            int n = Convert.ToInt32(Console.ReadLine());
            int x = 1, sum = 0;
            for (int i = 1; i <= n; i++)
            {
                x *= i;
                sum += x;
            }
            Console.WriteLine(sum);
            Console.ReadKey();
            /*******end********/

        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ch603
{
    class Program
    {
        static void Main(string[] args)
        {
            /******begin*******/
            int n = Convert.ToInt32(Console.ReadLine());
            int sum = 0;
            for (int i = 2; i <= n; i++)
            {
                bool b = true;
                for (int j = 2; j < i; j++)     //判断当前判断的数字是不是质数
                {
                    if (i % j == 0)     //说明不是质数
                    {
                        b = false;
                        break;
                    }
                }
                if (b == true)
                {
                    sum += i;
                }
            }
            Console.WriteLine($"素数的和：{sum}");
            Console.ReadKey();
            /*******end********/

        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ch604
{
    class Program
    {
        static void Main(string[] args)
        {
            /******begin*******/
            int n = Convert.ToInt32(Console.ReadLine());
            int r, m, j = 1;
            do
            {
                m = 0;
                for (int i = 1; i < j; i++)
                {
                    r = j % i;
                    if ((r == 0) == true)
                    {
                        m = m + i;
                    }
                }
                if ((m == j) == true)
                {
                    Console.WriteLine(j);
                }
                j++;
            } while (j < n);
            /*******end********/

        }
    }
}