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Wilf’s conjecture for all numerical semigroups

Prove or disprove Wilf’s conjecture by establishing whether every numerical semigroup S satisfies the inequality (F(S) + 1 − g(S)) / (F(S) + 1) ≥ 1 / e(S), where F(S) is the Frobenius number, g(S) is the genus, and e(S) is the embedding dimension.

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Background

The paper reviews core invariants of numerical semigroups—embedding dimension, Frobenius number, and genus—and recalls Wilf’s conjecture, which ties these three parameters via a density inequality. Despite substantial progress on related bounds and random models, Wilf’s conjecture remains a central open problem in the field.

The authors’ work focuses on probabilistic bounds in Erdős–Rényi-type random numerical semigroup models; however, Wilf’s conjecture concerns all numerical semigroups and stands independently of the random model considered here.

References

A central problem in numerical semigroups is to prove or disprove Wilf's conjecture which is that every numerical semigroup $S$ satisfies the inequality \frac{\F(S) + 1 - \g(S)}{\F(S)+1} \geq \frac{1}{\e(S)} .

Improved Upper Bounds on Key Invariants of Erdős-Rényi Numerical Semigroups (2411.13767 - Bogart et al., 21 Nov 2024) in Section 1 (Introduction)