from a purely mathematical standpoint, yes

from a practical engineering standpoint, no, it’s impossible

I’m pedantic as they come, but pedantry has little use in an engineering discipline, software engineering included

like, if I take a cup of water and pour it into the Pacific Ocean strictly speaking I can say I “single-handed raised the water level of the ocean” and you’d be correct in the most unhelpful way

for the code in question if the PRNG is working as expected then for all meaningful purposes it can be considered impossible

edit oh also to fight pedantry with pedantry, technically even a check that would prevent duplicates might not prevent duplicates because you could argue there’s a non-zero chance a random cosmic ray flips just the right bit at just the right moment rendering even that pure chance. anything engineered (and not pure mathematical theory) has to draw the line of plausibility somewhere because we’re engineering inside of a chaotic reality. drawing the line to say that the image above is functionally impossible is just fine.