做一个函数yanghuiTriangle(n,i)表示得到n层下标为i的数字。

    <script>
        function yanghuiTriangle(n, i)
        {
            if(n == 0 || i == 0 || n == i)
            {
            	return 1;
            }

            return yanghuiTriangle(n-1, i) + yanghuiTriangle(n - 1, i - 1);
	}

	var row = 9;

	for(var n = 0 ; n <= row ; n++)
	{
		var str = "";
		str += "\t".repeat(row - n);

		for(i = 0 ; i <= n ; i++)
		{
		  str += yanghuiTriangle(n,i) + "\t\t";
		}

	    console.log(str);
	}
    </script>