sorry if i didn't answer your question initially. the thing is... that being random can mean, well... anything. it could mean they could all be the same number, or they could all be completely different numbers for each iteration.

my guess is that you are interested in having different numbers. in this case you would want to determine the random variance of the set of numbers. This will tell you how spread out the numbers are. You could also possibly take the correlation of all of your points (plotted on a graph). The lower the correlation the less related each iteration is to one another; but i'm not really sure if that's a good measure of randomness.

sorry if i still didn't answer your question, statistics never really was my strong point. i still think your best bet is to seek out other algorithms and see which one works best. if you don't have a lot of math background, it might be tough deciphering all the equations. but anyways, i hope this gives you some more insight about all of this.