The Terwilliger algebra of an almost-bipartite P- and Q-polynomial association scheme

dc.creatorCaughman, John S.
dc.creatorMacLean, Mark S.
dc.creatorTerwilliger, Paul M.
dc.date2005-08-22
dc.date.accessioned2026-07-07T05:22:33Z
dc.date.available2026-07-07T05:22:33Z
dc.descriptionLet $Y$ denote a $D$-class symmetric association scheme with $D \geq 3$, and suppose $Y$ is almost-bipartite P- and Q-polynomial. Let $x$ denote a vertex of $Y$ and let $T=T(x)$ denote the corresponding Terwilliger algebra. We prove that any irreducible $T$-module $W$ is both thin and dual thin in the sense of Terwilliger. We produce two bases for $W$ and describe the action of $T$ on these bases. We prove that the isomorphism class of $W$ as a $T$-module is determined by two parameters, the dual endpoint and diameter of $W$. We find a recurrence which gives the multiplicities with which the irreducible $T$-modules occur in the standard module. We compute this multiplicity for those irreducible $T$-modules which have diameter at least $D-3$.
dc.description22 pages
dc.identifierhttps://arxiv.org/abs/math/0508401
dc.identifierhttp://arxiv.org/abs/math/0508401
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/76106
dc.subjectCombinatorics
dc.subjectRepresentation Theory
dc.subject05E30
dc.titleThe Terwilliger algebra of an almost-bipartite P- and Q-polynomial association scheme
dc.typetext

Files

Collections