Transactions of the American Mathematical Society

Author(s): Nathan Reading
Journal: Trans. Amer. Math. Soc. 359 (2007), 5931-5958.
MSC (2000): Primary 20F55; Secondary 05E15, 05A15
Posted: June 27, 2007
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Abstract: We introduce Coxeter-sortable elements of a Coxeter group

For finite

we give bijective proofs that Coxeter-sortable elements are equinumerous with clusters and with noncrossing partitions. We characterize Coxeter-sortable elements in terms of their inversion sets and, in the classical cases, in terms of permutations.

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Nathan Reading
Affiliation: Department of Mathematics, University of Michigan, Ann Arbor, Michigan 48109-1043
Address at time of publication: Department of Mathematics, North Carolina State University, Raleigh, North Carolina 27695-8205
Email: nreading@umich.edu, nathan_reading@ncsu.edu

DOI: 10.1090/S0002-9947-07-04319-X
PII: S 0002-9947(07)04319-X
Received by editor(s): August 18, 2005
Posted: June 27, 2007
Additional Notes: The author was partially supported by NSF grant DMS-0202430.
Copyright of article: Copyright 2007, Nathan Reading

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