Let's say I ask a question and accept an answer. Then I decide the answer doesn't fully satisfy me and the reason is that my question should be slightly more specific. Is it appropriate to edit the question and then accept a new answer or should I post the edited question separately with a link to the original one?
Example. Let's say I ask for an example of an even number and accept an answer that says $6$ then decide what I wanted to ask was for a power of $2$.
The reason I am asking is somewhat more subtle than the above example. Some time ago I asked for a property of numbers in $\mathbb{N}$ such that we know is satisfied at least by a number but we don't even have a bound for one such number. I now would like to add the condition that this property is such that for any $n\in \mathbb{N}$ we have a way of checking whether $n$ satisfies it.
I've already asked the author of the accepted answer about the edited question in a comment. My doubt would be about what to do if he cannot answer it.
