1. On pure \(\kappa \)-sparse gapsets

   • Gilberto B. Almeida Filho
   • Matheus Bernardini

   Research Article 15 February 2022 Pages: 213 - 227

2. Set-theoretic solutions of the Yang–Baxter equation associated to weak braces

   • Francesco Catino
   • Marzia Mazzotta
   • Paola Stefanelli

   Research Article Open access 11 March 2022 Pages: 228 - 255

3. On the asymptotic behaviour of semigroups for flows in infinite networks

   • Alexander Dobrick

   Research article Open access 04 February 2022 Pages: 256 - 280

4. Pseudogroups and their torsors

   • Jonathon Funk
   • Pieter Hofstra

   Research Article 10 March 2022 Pages: 281 - 319

5. On diagram groups over Fibonacci-like semigroup presentations and their generalizations

   • V. S. Guba

   Research Article 08 October 2021 Pages: 320 - 329

   

6. Numerical semigroups generated by quadratic sequences

   • Mara Hashuga
   • Megan Herbine
   • Alathea Jensen

   Research Article 07 March 2022 Pages: 330 - 357

   

7. Various types of completeness in topologized semilattices

   • Konstantin Kazachenko
   • Alexander V. Osipov

   Research Article 07 March 2022 Pages: 358 - 375

   

8. The monoid of orientation-preserving k-extensive transformations

   • De Biao Li
   • Wen Ting Zhang
   • Yan Feng Luo

   Research Article 04 March 2022 Pages: 376 - 397

   

9. Topologies on the symmetric inverse semigroup

   • J. Pérez
   • C. Uzcátegui

   Research Article 27 January 2022 Pages: 398 - 414

10. Density of type-dependent sets in Krull monoids with analytic structure

    • Maciej Radziejewski

    Research Article Open access 30 December 2021 Pages: 415 - 447

11. Self-similar monoids related to Hahn groups

    • Wolfgang Rump

    Research Article 14 March 2022 Pages: 448 - 463

    

12. Property A for hypergroups

    • Seyyed Mohammad Tabatabaie
    • Massoud Amini
    • Ali Asghar Amjadi

    Research Article 28 January 2022 Pages: 464 - 479

13. Abundance of the ideals of the order-preserving and decreasing full transformation semigroup

    • Jing Yang
    • Xiuliang Yang

    Research Article 07 February 2022 Pages: 480 - 493

14. The ideals of the monoid of all partial order-preserving extensive transformations

    • Ping Zhao
    • Huabi Hu
    • Yunyun Qu

    Research Article 10 March 2022 Pages: 494 - 508

15. Orientation-preserving and orientation-reversing mappings: a new description

    • Peter M. Higgins
    • Alexei Vernitski

    Short Note Open access 19 February 2022 Pages: 509 - 514

    

16. Publisher Correction to: Topologies on the symmetric inverse semigroup

    • J. Pérez
    • C. Uzcátegui

    Publisher Correction 16 March 2022 Pages: 515 - 515

17. Publisher Correction to: On the semigroup of order-preserving partial isometries of a finite chain with restricted range

    • Worachead Sommanee
    • Jintana Sanwong

    Publisher Correction 15 February 2022 Pages: 516 - 516

18. Editorial Note

    • Mikhail Volkov

    Editorial Note 31 January 2022 Pages: 517 - 517