Symmetric Chain Decomposition and El-shellability of Ding Order
نویسنده
چکیده
We show that Ding's partial order on maximal rook placements on any Ferrers board has a symmetric chain decomposition and is EL-shellable. As a consequence the partial order is Peck, and we show that it has Mobius function values of 1; 0 or +1.
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