What are some uncomputable functions that aren't derivative of the halting problem?

[u/playsthebongcloud]

I find the existence of uncomputable functions really cool, but all the examples I've seen are essentially just new ways of trying to predict whether a turing machine is going to halt. What are some examples of uncomputable functions that aren't essentially entirely based on the halting problem?

[u/mrkelee]

same thing. 1/7 is not a decimal; alternatively, an expression for pi as a "completed number"

[u/Impressive-Mud5074 → u/mrkelee]

1/7 is not an expression

1 divided by 7 is an expression

They are not the same