Abacus Models for Parabolic Quotients of Affine Weyl Groups
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چکیده
We introduce abacus diagrams that describe the minimal length coset representatives of affine Weyl groups in types C̃/C, B̃/D, B̃/B and D̃/D. These abacus diagrams use a realization of the affine Weyl group C̃ due to Eriksson to generalize a construction of James for the symmetric group. We also describe several combinatorial models for these parabolic quotients that generalize classical results in type à related to core partitions.
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تاریخ انتشار 2012