Java求阶乘和

   public static int sumFactorial(int n) {
        //求1！+2！+3！+4！+........+n!的和
        int sum = 0;
        for (int i = 1; i <= n; i++) {
            sum += factorial(i);
        }
        return sum;
    }

    public static int factorial(int n) {
        //求n！
        if (n == 1) {
            return 1;
        }
        return n*factorial(n-1);
    }
    public static void main(String[] args) {

        System.out.println(sumFactorial(3));
    }

输出结果：