Ways to include unsolved problem in research paper

Question

Currently i am writing a paper in which i have proved a result but i have the extension of the same result which i think should be true but i could not prove it. I want to leave it for readers of my papers.

what are some good ways to write an unsolved problem in research paper?

Any example of old papers would be helpful.Thanks

Answer 1

You write something like "Having proved Theorem 3.2, it's natural to ask whether every snorkle is in fact redundant. This is clearly the case in dimensions 1 and 2, and the Riemann hypothesis implies the results in dimensions 7 and higher, as we'll now show, but for dimensions $3$ through $6$, the question remains open, and even in dimensions $7$ and higher, there may be a far simpler proof than the one that would result from any proof of RH. Section 8 addresses these topics briefly, with a few ideas on possible approaches."

Answer 2

Learn from the old masters:

"In fact a more general result is true. I have a truly marvelous proof of this more general theorem which this margin is too narrow to contain."

:)