Research Article

Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers

Volume: 21 Number: 1 March 30, 2026
TR EN

Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers

Abstract

This paper investigates the interplay between numerical semigroups and enumerative combinatorics through the lens of Young diagrams, rook polynomials, and the Lah numbers. For a given numerical semigroup S, we associate a Young diagram constructed from the gap set of S. We then compute the rook polynomial corresponding to this diagram and analyze its coefficients. It is observed that these coefficients exhibit a strong connection with the Lah numbers, which count ordered partitions. Our approach introduces a new combinatorial interpretation of numerical semigroup gaps and reveals novel structural links between algebraic and enumerative concepts.

Keywords

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Ethical Statement

Ethical declaration is not required

Thanks

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References

  1. Rosales JC, García-Sánchez PA. Numerical Semigroups. New York, NY, USA: Springer, 2009.
  2. Kirfel C, Pellikaan R. The minimum distance of codes in an array coming from telescopic semigroups. IEEE Trans Inf Theory 1995; 41(6): 1720-1732.
  3. Keith WJ, Nath R. Partitions with prescribed hooksets. arXiv preprint 2010; arXiv:1011.1945
  4. Constantin H, Houston-Edwards B, Kaplan N. Numerical sets, core partitions, and integer points in polytopes. Combinatorial and Additive Number Theory II. Ed. Nathanson MB. New York: Springer International Publishing, 2017; 99-127.
  5. Süer M, Yeşil M. Symmetric and pseudo-symmetric numerical semigroups via Young diagrams and their semigroup rings. J Korean Math Soc 2021; 58(6):1367-1383.
  6. Riordan J. An Introduction to Combinatorial Analysis. New York, NY, USA: Wiley Press, 1958.
  7. Guo BN, Qi F. Six proofs for an identity of the Lah numbers. Online Journal of Analytic Combinatorics Press 2015; 10: 5 pages.
  8. Haglund J. q-Rook polynomials and matrices over finite fields. Adv Appl Math 1998; 20(4): 450–487.

Details

Primary Language

English

Subjects

Algebra and Number Theory, Combinatorics and Discrete Mathematics (Excl. Physical Combinatorics)

Journal Section

Research Article

Early Pub Date

December 16, 2025

Publication Date

March 30, 2026

Submission Date

June 20, 2025

Acceptance Date

September 24, 2025

Published in Issue

Year 2026 Volume: 21 Number: 1

APA
Süer, M. (2026). Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers. Turkish Journal of Science and Technology, 21(1), 35-45. https://doi.org/10.55525/tjst.1724097
AMA
1.Süer M. Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers. TJST. 2026;21(1):35-45. doi:10.55525/tjst.1724097
Chicago
Süer, Meral. 2026. “Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers”. Turkish Journal of Science and Technology 21 (1): 35-45. https://doi.org/10.55525/tjst.1724097.
EndNote
Süer M (March 1, 2026) Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers. Turkish Journal of Science and Technology 21 1 35–45.
IEEE
[1]M. Süer, “Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers”, TJST, vol. 21, no. 1, pp. 35–45, Mar. 2026, doi: 10.55525/tjst.1724097.
ISNAD
Süer, Meral. “Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers”. Turkish Journal of Science and Technology 21/1 (March 1, 2026): 35-45. https://doi.org/10.55525/tjst.1724097.
JAMA
1.Süer M. Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers. TJST. 2026;21:35–45.
MLA
Süer, Meral. “Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers”. Turkish Journal of Science and Technology, vol. 21, no. 1, Mar. 2026, pp. 35-45, doi:10.55525/tjst.1724097.
Vancouver
1.Meral Süer. Combinatorial Insights into Numerical Semigroups: Rook Placements and Lah Numbers. TJST. 2026 Mar. 1;21(1):35-4. doi:10.55525/tjst.1724097