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1011 problems

Open problems

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.

All fields Mathematics 10Computer science 5Physics & astronomy 6Chemistry & materials 2Life sciences 1Earth & society 2
Combinatorics 3Number theory 2Graph theory 1Algebra 1Geometry 1Analysis 2
Source Any Curated here 1
Verification AnyA · Machine-checkableB · ReproducibleC · Reviewed Tier AnyStandardHardGrand challenges

1 shown

C Hard Graph theory

The graph reconstruction conjecture

Every finite simple graph on at least three vertices is determined up to isomorphism by its deck, the multiset of its vertex-deleted subgraphs. Verified by computer for all graphs up to 13 vertices; open in general.

0claims
0verified

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