The Möbius function of a composition poset
نویسندگان
چکیده
We determine the Möbius function of a poset of compositions of an integer. In fact we give two proofs of this formula, one using an involution and one involving discrete Morse theory. This composition poset turns out to be intimately connected with subword order, whose Möbius function was determined by Björner. We show that using a generalization of subword order, we can obtain both Björner’s results and our own as special cases.
منابع مشابه
The Möbius function of the composition poset
We determine the Möbius function of the poset of compositions of an integer. In fact we give two proofs of this formula, one using an involution and one involving discrete Morse theory. The composition poset turns out to be intimately connected with subword order, whose Möbius function was determined by Björner. We show that using a generalization of subword order, we can obtain both Björner’s ...
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