Are you talking about FRACTRAN? Halting problem being reduced to [subset of collatz-like problems] says nothing about uncomputability of [all the rest of colla

Are you talking about FRACTRAN? Halting problem being reduced to [subset of collatz-like problems] says nothing about uncomputability of [all the rest of collatz-like problems] and even less about [does single specific collatz-like problem halt] The only consquence is that "most general" definition of collatz-like problem as a whole is uncomputable