Abstract

Around 2001 we classified the Leonard systems up to isomorphism. The proof was lengthy and involved considerable computation. In this paper we give a proof that is shorter and involves minimal computation. We also give a comprehensive description of the intersection numbers of a Leonard system.

Highlights

  • In the area of Algebraic Combinatorics there is an object called a commutative association scheme [2, 13]

  • This thesis helped to motivate the work of Bannai [2, p. i], who taught a series of graduate courses on commutative association schemes during September 1978–December 1982 at the Ohio State University

  • In [18, Appendix A] and [20, Sect. 19], a bijection is given between the isomorphism classes of Leonard systems over R, and the orthogonal polynomial systems that satisfy Askey-Wilson duality

Read more

Summary

Introduction

In the area of Algebraic Combinatorics there is an object called a commutative association scheme [2, 13]. Assumption on d and explicitly describes all the limiting cases that show up This version gives a complete classification of the orthogonal polynomial systems that satisfy Askey-Wilson duality. 19], a bijection is given between the isomorphism classes of Leonard systems over R, and the orthogonal polynomial systems that satisfy Askey-Wilson duality. Appearing in [14] is the correspondence between Leonard pairs over R and the orthogonal polynomial systems that satisfy Askey-Wilson duality. Turning to the present paper, we obtain two main results: (i) an improved proof for the classification of Leonard systems; (ii) a comprehensive description of the intersection numbers of a Leonard system. Concerning our second main result, we mentioned earlier that the Leonard systems correspond to the orthogonal polynomial sequences that satisfy Askey-.

Preliminaries
Pre Leonard Systems
The Antiautomorphism y
Normalizing Idempotents
Normalizing Idempotents and Decompositions
A Result About Wrap-Around
The Parameter Array of a Leonard System
10 Statement of the Leonard System Classification
11 Recurrent Sequences
12 Recurrent Sequences in Closed Form
18 Characterizations of Leonard Systems and Parameter Arrays
19 The Intersection Numbers
À sÃq2

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.