public void GetFactorialTest()
        {
            var fact0 = LocalFunctions.GetFactorial(0);

            Assert.Equal(1, fact0);

            var fact1 = LocalFunctions.GetFactorial(1);

            Assert.Equal(1, fact1);

            var fact2 = LocalFunctions.GetFactorial(2);

            Assert.Equal(2, fact2);

            var fact10 = LocalFunctions.GetFactorial(10);

            Assert.Equal(3628800, fact10);

            long fact13 = LocalFunctions.GetFactorial(13);

            Assert.Equal(6227020800, fact13);
        }