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The archive grows because solvers add to it. Everything submitted is reviewed before it goes live.

Propose a problem

Original, or from a contest not yet archived. Reviewers check for duplicates and assign a provisional rating.

Maths goes in $…$, or $$…$$ on its own line. Problems with parts can use \begin{enumerate} and \begin{itemize} with \item, including labels of your own such as \item[(a)]; the preview shows them as real lists. Needs a diagram? Paste the TikZ for it here, in the statement or the solution. The preview below will show it as plain code rather than a picture. A reviewer renders it properly before the problem is published.
Your best guess. A reviewer sets the published rating, and the archive recalibrates it from how solvers actually do.
Required. A reviewer uses it to check your answer, and if the problem is accepted it becomes the first comment on it, credited to you. Nobody sees it until they have solved the problem or given up, so it will not spoil anything. TikZ is welcome here too; a reviewer renders it before publishing.
Optional. Shown under the statement in smaller type if the problem is published. Use it where a source would be wrong but the problem was not quite yours, or to clarify something the statement should not have to carry.
Required: at least one. Type a topic and press Enter; suggestions come from topics already in the archive, but a new name is fine.
Preview

This is how a reviewer, and eventually a solver, will see it. You will be asked to check it once more when you submit.

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Something missing, something broken, or a rating that looks wrong. Every note reaches the team.

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