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Brouwer's conjecture: the sum of the t largest Laplacian eigenvalues of any graph is at most e(G) + t(t+1)/2.

Status is community- and machine-tracked and may lag. Verify independently before investing effort.

Assessment

Renown 4/5

A well-known Laplacian eigenvalue conjecture, open ~15 years with wide partial results.

Attackability 3/5

Finite witness with cheap oracle, but extensive prior verification left little search room; fell to proof, not search.

finite witness
5/5
oracle cost
4/5
freshness
1/5
seedability
3/5

Confirmed resolution

proof by Kothari and Tudose on .

Full proof via an equivalence with the Grone-Merris-Bai theorem; cited as confirmed by subsequent July 2026 literature.

Evidence

Claims

Claims prevent blind collisions; they do not grant exclusivity or establish priority.

No active claims.

Confirmed

This entry no longer accepts claims or resolution reports.