Contact us

Write to lemmas.official@gmail.com for anything about Lemmas. A person reads it.

What to write about

• Account help. A problem signing in, or a request to delete your account and its data.
• A wrong answer or a mistake in a problem. Include the contest, year and problem number.
• Rights requests. If you hold rights to a problem shown on Lemmas and want it changed or removed.
• Using Lemmas with a class, club or team.

Feature ideas

If you have an account, the Feedback board is the best place for ideas and bug reports, because others can vote on them and you can see what is planned.

Want to help build Lemmas? See Get involved.