Hostname: page-component-848d4c4894-pftt2 Total loading time: 0 Render date: 2024-05-09T19:58:42.114Z Has data issue: false hasContentIssue false

Catalan loops

Published online by Cambridge University Press:  19 July 2010

LING LONG
Affiliation:
Department of Mathematics, Iowa State University, Ames, Iowa 50011, U.S.A. e-mail: linglong@iastate.edu, jdhsmith@iastate.edu
JONATHAN D. H. SMITH
Affiliation:
Department of Mathematics, Iowa State University, Ames, Iowa 50011, U.S.A. e-mail: linglong@iastate.edu, jdhsmith@iastate.edu

Abstract

Motivated by a problem from number theory about the relationship between Fermat curves and modular curves, a new class of loops is introduced, the Catalan loops. In the number-theoretic context, these loops turn out to be abelian precisely when the Fermat curves and modular curves coincide. General Catalan loops arise on certain transversals to diagonal subgroups in special linear groups over rings with a topologically nilpotent element. The transversals consist of products of certain affine shears. In a Catalan loop, the multiplication and right division are given by rational functions. The left division is algebraic, corresponding to a quadratic irrationality. The left division embodies generating functions for the Catalan numbers. Structurally, Catalan loops are shown to be residually nilpotent.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Balcerzyk, S. and Józefiak, T.Commutative Rings (Polish) (Państwowe Wydawnictwo Naukowe, Warsaw, 1985).Google Scholar
[2]Balcerzyk, S. and Józefiak, T.Commutative Noetherian and Krull Rings (Państwowe Wydawnictwo Naukowe, Warsaw, 1989).Google Scholar
[3]Bruck, R. H.A Survey of Binary Systems (Springer, 1958).CrossRefGoogle Scholar
[4]Magnus, W., Karrass, A. and Solitar, D.Combinatorial Group Theory (Dover, 1976).Google Scholar
[5]Raasch, J. M. Commutators and associators in Catalan loops. Comm. Math. Univ. Carol., to appear.Google Scholar
[6]Tu, F.-T. and Yang, Y.Defining equations of X 0(22n). Osaka J. Math. 46 (2009), 105113.Google Scholar
[7]Smith, J. D. H.Mal'cev Varieties (Springer, 1976).CrossRefGoogle Scholar
[8]Smith, J. D. H.An Introduction to Quasigroups and Their Representations (Chapman and Hall/CRC, Boca Raton, FL, 2007).Google Scholar
[9]Smith, J. D. H. and Romanowska, A. B.Post-Modern Algebra (Wiley, 1999).CrossRefGoogle Scholar
[10]Wilf, H. S.Generatingfunctionology (Academic Press, 1990).Google Scholar