I spent an afternoon once playing Infinite Craft, which uses some sort of LLM behind the scenes to do it's combinations.
At one point I got 007, and found 007+007 = 0014.
The maths gets wild though, and because it's been trained on text, it has no idea when it comes to combinations of numbers it hasn't seen before. I spent ages trying to get it to 69420 and just couldn't, although I could get 42069.