public static void FindPrimeThread2()
        {
            PrimeNumberCalc calc = new PrimeNumberCalc();

            Console.WriteLine(calc.FindPrimeNumber(400000));
            Console.WriteLine(DateTime.Now);
        }
        public static void FindPrimeThread1()
        {
            PrimeNumberCalc calc = new PrimeNumberCalc();

            Console.WriteLine(calc.FindPrimeNumber(250000));
        }