Abstract
We provide an expression for the conductor \(c(\varDelta )\) of a semimodule \(\varDelta \) of a numerical semigroup \(\varGamma \) with two generators in terms of the syzygy module of \(\varDelta \) and the generators of the semigroup. In particular, we deduce that the difference between the conductor of the semimodule and the conductor of the semigroup is an element of \(\varGamma \), as well as a formula for \(c(\varDelta )\) in terms of the dual semimodule of \(\varDelta \).
References
Brauer, A., Shockley, J.E.: On a problem of Frobenius. J. Reine Angew. Math. 211, 215–220 (1962)
Curtis, F.: On formulas for the Frobenius number of a numerical semigroup. Math. Scand. 67(2), 190–192 (1990)
Moyano-Fernández, J.J., Uliczka, J.: Hilbert depth of graded modules over polynomial rings in two variables. J. Algebra 373, 130–152 (2013)
Moyano-Fernández, J.J., Uliczka, J.: Lattice paths with given number of turns and numerical semigroups. Semigroup Forum 88(3), 631–646 (2014)
Moyano-Fernández, J.J., Uliczka, J.: Duality and syzygies for semimodules over numerical semigroups. Semigroup Forum 92(3), 675–690 (2016)
Ramírez Alfonsín, J.L.: The Diophantine Frobenius Problem, Oxford Lecture Series in Mathematics and its Applications, vol. 30. Oxford University Press, Oxford (2005)
Rosales, J.C., García Sanchez, P.A.: Numerical Semigroups. Springer, New York (2009)
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by Jorge Almeida.
Dedicated to the memory of Fernando Eduardo Torres Orihuela
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
The first named author was partially supported by Spanish Goverment, Ministerios de Ciencia e Innovación y de Universidades MTM2016-76868-C2-1-P. The second named author was partially supported by the Spanish Government, Ministerios de Ciencia e Innovación y de Universidades, grant PGC2018-096446-B-C22, as well as by Universitat Jaume I, grant UJI-B2018-10.
Rights and permissions
About this article
Cite this article
Almirón, P., Moyano-Fernández, J.J. A formula for the conductor of a semimodule of a numerical semigroup with two generators. Semigroup Forum 103, 278–285 (2021). https://doi.org/10.1007/s00233-021-10182-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00233-021-10182-1