Left-Modular Elements of Lattices
โ Scribed by Shu-Chung Liu; Bruce E. Sagan
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 168 KB
- Volume
- 91
- Category
- Article
- ISSN
- 0097-3165
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โฆ Synopsis
Left-modularity is a concept that generalizes the notion of modularity in lattice theory. In this paper, we give a characterization of left-modular elements and derive two formulae for the characteristic polynomial, /, of a lattice with such an element, one of which generalizes Stanley's theorem [6] about the partial factorization of / in a geometric lattice. Both formulae provide us with inductive proofs for Blass and Sagan's theorem [2] about the total factorization of / in LL lattices. The characteristic polynomials and the Mo bius functions of non-crossing partition lattices and shuffle posets are computed as examples.
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