Gaussea is made to test your skills on mathematical olympiad-like challenges. Some challenges will come exclusively from one problem of some classic olympiad competition, and some will be a mix of them.
The problems start easy, and gradually tend to challenges that might require several hours to solve them. A list of useful resources is linked, to help you progress, and learn as you explore the website. Most times, the key is to play with the objects the challenges involve.
You are only asked to enter a single number at the end, which might be an integer or a decimal number. Sometimes, the numbers also get huge, with exponentiation for example, and that's why we sometimes need to take the result modulo some other integer. You can access a simple calculator in each page, which can help you find the required answer if you have a formula for the general problem.
Be aware that I welcome any new problem to the website, feel free to contact me, either on discord (@pacome.f), or by mail, at pacomefromager at icloud dot com.
For problems not having enough solves, a default difficulty is used, and once a problem is considered to have enough solvers, the difficulty is computed, in a way that takes into account the total number of solves on the website, and the attention the problem has received. It means that the difficulty of a problem can change over time.