[73] If there exists b = lim f(x_n) for an arbitrary sequence (x_n| x_n → a, n → ∞), then b is unique for all (x_n).

https://www.evernote.com/shard/s29/sh/cd85a330-27a7-48ef-bf8d-112d0a80acf5/1b5a733aead4e22bfb97a5f2d5cdc530