gistfile1.txt

var n = 5;
var red="FF0000";
var blue="87CEFA";
var green="00FF00";
var purple="A020F0";
var orange="FFA500";
var yellow="FFFF00";

document.writeln("<table class=\"school\" id=\"sumtable\">");
var tableid=document.getElementById("sumtable");
var rows=tableid.getElementsByTagName("tr");
var color = "red";
var ids=1;
var el;

document.writeln("<tr>");
document.write("<th>");
document.write("+");
document.write("</th>");
for (i = 0; i <= n; i++) {
    document.write("<th>");
    document.write(i);
    document.write("</th>");
}
document.writeln("</tr>");


for (i = 1; i <= n+1; i++) {
    document.writeln("<tr>");
    for (j = -1; i+j-1 <= n; j++) {
        if (j == -1) {
            document.write("<th>");
            document.write(i+j);
            document.write("</th>");
        } else {
	    document.write("<td id=\"" + ids + "\">");
	    el = document.getElementById(ids);
	    switch (i+j-1) {
	    case 0:
		el.style.backgroundColor="#" + red.toString(16);
		break;
	    case 1:
		el.style.backgroundColor="#" + purple.toString(16);
		break;
	    case 2:
		el.style.backgroundColor="#" + blue.toString(16);
		break;
	    case 3:
		el.style.backgroundColor="#" + orange.toString(16);
		break;
	    case 4:
		el.style.backgroundColor="#" + yellow.toString(16);
		break;
	    case 5:
		el.style.backgroundColor="#" + green.toString(16);
		break;
	    }
	    ids++;
	    document.write(i+j-1);
	    document.write("</td>");
	}
    }
    document.writeln("</tr>");
}
document.writeln("</table>");