WARNING: HERE COMES SCIENCE There are 25 exotic weapons in the game. Fate of All Fools, Vex, and Necrochasm are obtained through the raid or unavailable. This leaves 22. 5 guns can only be obtained through bounties, so that leaves 17. 3 guns are PS Exclusive and Xur can't sell them ATM, so that leaves 14. This means that, assuming Xur is RNG, each weapon has A 7.14% probability of being sold each week. With each gun having a 0.071 chance of being sold, we have to calculate the probability of the same gun being sold more than once consecutively. The most times that this has happened was 2 weeks in a row. The compound probability of this happening is of 0.504% in layman terms, this means that it should happen once approximately every 4 years. Low probability but still plausible RNG. NOW... When we take into account ARMOR things get a bit trickier. There are 26 pieces of exotic armor ALL of which can be sold by Xur. This means that each individual piece of armor has 3.84% probability of being sold by Xur. With each piece of armor having a 0.038 chance of being sold, what is the probability of the same piece of armor being sold in consecutive weeks? Well, the most that this has happened was 4 times. The compound probability of this happening is of 0.000208% This means that if Xur was RNG, this should happen once approximately... Every 10,000 years. Now, I will save the boring explanation and just jump to conclusion. Since Xur has sold the exact same inventory with same stats on armor more than once, the probability is too small to put on this article, but it should happen once ever 21,477,719,412 years (if you consider that the Big Bang is theorized to have happened 13.1 Billion years ago, that's longer than the universe has existed... By 1.6 times! I'm not giving an opinion, I just did the basic math. You make up your own mind.