Perhaps oddly, this is passage of science fiction that has stuck with me most over the past decade. It was the first time I viscerally felt the different between human time and machine time, and this likely understates it.
It’s not the more narratively engaging book (a lot of AI to AI communication) but the insights are pretty fascinating. Would definitely recommend it with the narrative caveat.
Seen the 1966 book Colossus by Dennis Feltham Jones or the excellent 1970 film version Colossus: The Forbin Project? Part of that story involves 2 AIs developing an "intersystem language" that only they can understand. Someone made a great video summary: