Not sure if this is what you want, but this will display the first 50 numbers (if you use firefox you could put it all on one line and paste "javascript:<code>" into the address bar for it to show):
code:
var s = "";
var url = "http://xxxxxx.com/rxxxx/AAA";
var start = 399495790;
for(var i = 0; i < 50; i++) {
s += url + (start + i) + "<br/>";
}
document.write(s);
Change the
399495790 to change the first number it displays and the
50 to change how many it displays.