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A generalization of Wilf’s conjecture for generalized numerical semigroups

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Abstract

A numerical semigroup is a submonoid of \({\mathbb {N}}\) with finite complement in \({\mathbb {N}}\). A generalized numerical semigroup is a submonoid of \({\mathbb {N}}^{d}\) with finite complement in \({\mathbb {N}}^{d}\). In the context of numerical semigroups, Wilf’s conjecture is a long standing open problem whose study has led to new mathematics and new ways of thinking about monoids. A natural extension of Wilf’s conjecture, to the class of \({\mathcal {C}}\)-semigroups, was proposed by García-García, Marín-Aragón, and Vigneron-Tenorio. In this paper, we propose a different generalization of Wilf’s conjecture, to the setting of generalized numerical semigroups, and prove the conjecture for several large families including the irreducible, symmetric, and monomial case. We also discuss the relationship of our conjecture to the extension proposed by García-García, Marín-Aragón, and Vigneron-Tenorio.

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References

  1. Atiyah, M.F., Macdonald, I.G.: Introduction to Commutative Algebra. Addison-Wesley Publishing Company, Boston (1969)

    MATH  Google Scholar 

  2. Bras-Amorós, M.: The ordinarization transform of a numerical semigroup and semigroups with a large number of intervals. J. Pure Appl. Algebra 213, 2507–2518 (2012)

    Article  MathSciNet  Google Scholar 

  3. Cisto, C., Delgado, M., García-Sánchez, P.A.: Algorithms for Generalized Numerical Semigroups. arXiv:1907.02461 (2019)

  4. Cisto, C., Failla, G., Utano, R.: On the generators of a generalized numerical semigroup. Analele Univ. “Ovidius” 27(1), 49–59 (2019)

    MathSciNet  MATH  Google Scholar 

  5. Cisto, C., Failla, G., Peterson, C., Utano, R.: Irreducible generalized numerical semigroups and uniqueness of the Frobenius element. Semigroup Forum 99(2), 481–495 (2019)

    Article  MathSciNet  Google Scholar 

  6. Cox, D., Little, J., O’Shea, D.: Ideals, Varieties, and Algorithms, Undergraduate Texts in Mathematics. Springer, Berlin (2007)

    Book  Google Scholar 

  7. Delgado, M.: Conjecture of Wilf: A Survey. arXiv:1902.03461 (2019)

  8. Delgado, M., García-Sánchez, P.A., Morais, J.: NumericalSgps, A Package for Numerical Semigroups, Version 1.1.11. https://gap-packages.github.io/numericalsgps (2019). (Refereed GAP package)

  9. Dobbs, D., Matthews, G.M.: On a question of Wilf concerning numerical semigroups. In: Badawi, A. (ed.) Focus on Commutative Rings Research, pp. 193–202. Nova Science Publishers, New York (2006)

    Google Scholar 

  10. Eliahou, S.: Wilf’s conjecture and Macaulay’s theorem. J. Eur. Math. Soc. (JEMS) 20(9), 2105–2129 (2018)

    Article  MathSciNet  Google Scholar 

  11. Failla, G., Peterson, C., Utano, R.: Algorithms and basic asymptotics for generalized numerical semigroups in \(\mathbb{N}^{d}\). Semigroup Forum 92(2), 460–473 (2016)

    Article  MathSciNet  Google Scholar 

  12. The GAP Group, GAP -- Groups, Algorithms, and Programming, Version 4.10.2. https://www.gap-system.org (2019)

  13. García-García, J.I., Marín-Aragón, D., Vigneron-Tenorio, A.: An extension of Wilf’s conjecture to affine semigroups. Semigroup Forum 96(2), 396–408 (2018)

    Article  MathSciNet  Google Scholar 

  14. Hemmecke, R., Takemura, A., Yoshida, R.: Computing holes in semi-groups and its applications to transportation problems. Contrib. Discrete Math. 4(1), 81–91 (2009)

    MathSciNet  MATH  Google Scholar 

  15. Herzog, J., Moradi, S., Rahimbeigi, M., Soleyman Jahan, A.: On the Monomial Reduction Number of a Monomial Ideal in \(K[x,y]\). arXiv:1908.03765 (2019)

  16. Kaplan, N.: Counting numerical semigroups by genus and some cases of a question of Wilf. J. Pure Appl. Algebra 216, 1016–1032 (2012)

    Article  MathSciNet  Google Scholar 

  17. Rosales, J.C., García-Sánchez, P.A.: Numerical semigroups. Developments in Mathematics, vol. 20. Springer, New York (2009)

    Book  Google Scholar 

  18. Sammartano, A.: Numerical semigroups with large embedding dimension satisfy Wilf’s conjecture. Semigroup Forum 85, 439–447 (2012)

    Article  MathSciNet  Google Scholar 

  19. Swanson, I., Huneke, C.: Integral Closure of Ideals, Rings, and Modules, Volume 336 of London Mathematical Society Lecture Note Series. Cambridge University Press, Cambridge (2006)

    Google Scholar 

  20. Wilf, H.S.: A circle-of-lights algorithm for the money-changing problem. Am. Math. Mon. 85, 562–565 (1978)

    MathSciNet  MATH  Google Scholar 

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Correspondence to Michael DiPasquale.

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Communicated by Fernando Torres.

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The research that led to the present paper was partially supported by a grant of the group GNSAGA of INdAM. DiPasquale, Peterson, and Flores would like to thank the University of Messina for its financial support. The research of DiPasquale, Peterson, and Flores was also supported in part by NSF Grant DMS-1830676.

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Cisto, C., DiPasquale, M., Failla, G. et al. A generalization of Wilf’s conjecture for generalized numerical semigroups. Semigroup Forum 101, 303–325 (2020). https://doi.org/10.1007/s00233-020-10085-7

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  • DOI: https://doi.org/10.1007/s00233-020-10085-7

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