OpenAI reports balanced counterexamples to Ryser’s covering conjecture

For every sufficiently large prime q, a finite intersecting (q+1)-partite (q+1)-uniform hypergraph has covering number q+1 and exactly q+1 nonisolated vertices in each part.

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Understanding the problem

Read the background

For every sufficiently large prime q, a finite intersecting (q+1)-partite (q+1)-uniform hypergraph has covering number q+1 and exactly q+1 nonisolated vertices in each part.

Why it matters

If correct, disproves Ryser’s covering conjecture even with equal-sized vertex parts.

What counts as progress

Can an intersecting r-partite hypergraph require r vertices to cover despite Ryser’s conjectured r−1 bound?

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