I'm not a mathematician, but I would guess that the Surreal numbers developed by John Conway, do contain values that start with an infinite sequence of 0.9_ but

I'm not a mathematician, but I would guess that the Surreal numbers developed by John Conway, do contain values that start with an infinite sequence of 0.9_ but "end" with something that makes them != 1. https://en.m.wikipedia.org/wiki/Surreal_number https://en.m.wikipedia.org/wiki/Surreal_number