The Natural Number Game is a Lean4 tutorial hosted on the Lean Game Server, requiring JavaScript to run. It is maintained by Marcus Zibrowius at Heinrich-Heine-Universität Düsseldorf in Germany.
The Lean Game Server is a React-based web application that requires JavaScript to function. It is hosted in Germany and operated by Marcus Zibrowius at Heinrich-Heine-Universität Düsseldorf, with no personal data collected when JavaScript is disabled.