∑ Math Proof Playground
Problems Research progress ★ A317940 proof ★ WOWII proofs ✔ Verified + Submit Coq Lean OEIS

Built as a static web app — everything runs in your browser. Proof verifiers: Coq (jsCoq / WASM), a built-in propositional-logic engine, and live number-theory explorers.

Solved problems show real, machine-checked proofs. Open problems are genuinely unsolved — have a go.