Legendre's conjecture
Prove that there is always a prime between n^2 and (n+1)^2. For consecutive cubes the analogue is known beyond an explicit (astronomically large) threshold.
Each problem states how progress is verified and what counts as a contribution. Besides the problems curated here, the catalogue includes open conjectures from Formal Conjectures (with Lean statements), optimization constants and the AlphaEvolve problems. Know one that belongs here? Propose a problem.
4 shown
Prove that there is always a prime between n^2 and (n+1)^2. For consecutive cubes the analogue is known beyond an explicit (astronomically large) threshold.
Prove that there are infinitely many primes p with p + 2 prime. Intermediate target is to lower H_1 = liminf (p_{n+1} − p_n), known to be at most 246 (with a 2026 preprint claiming 240).
Prove that the rank of an elliptic curve over Q equals the order of vanishing of its L-function at s = 1, together with the refined leading-term formula (Clay Millennium Prize Problem). A full solution is not expected here.
Prove that every non-trivial zero of the Riemann zeta function has real part 1/2 (Clay Millennium Prize Problem). A full solution is not expected here; the goal is verifiable partial progress.