js之杨辉三角

<script>
        function test(n){
            if(n==1){
                document.write("1");
            }
            else if(n>1){
                document.write("&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp");
                document.write("1");
                document.write("&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp");
                document.write("<br/>");
                for(var i=1; i<=n; i++){
                    document.write("&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp");
                    document.write(String(1));
                    document.write("&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp");
                    for(var j=1;j<=i;j++){
                        var re;
                        re=jc(i)/(jc(j)*jc(i-j));
                        document.write("&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp");
                        document.write(String(re));
                        document.write("&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp");
                    }
                    document.write("<br/>");
                }
            }
        }
        function jc(n){
            if(n==0){
                return 1;
            }
            else if(n==1) {
                return 1;
            }
            else if(n>=1){
                return n*jc(n-1);
            }
            else{
                return 0;
            }
        }

        function test1(){
            document.write("<Div align=\"center\">");
            test(9);
            document.write("</Div>");
        }
        test1();

    </script>