The skeletons of free distributive lattices are studied by methods of formal concept analysis; in particular, a specific closure system of sublattices is elaborated to clarify the structure of the skeletons. Up to five generators, the skeletons are completely described.
The level polynomials of the free distributive lattices
โ Scribed by George Markowsky
- Publisher
- Elsevier Science
- Year
- 1980
- Tongue
- English
- Weight
- 915 KB
- Volume
- 29
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
โฆ Synopsis
We show that there exist a set of polynomials {Lk 1 k = 0, 1 * * a} such that L,(n) is the number of elements of rank k in the free distributive lattice on n generators. L,(n) = L,(n) = 1 for all n and the degree of L, is k -1 for k 5 1. We show that the coefficients of the L, can be calculated using another family of polynomials, Pi. We show how to calculate L, for k = 1 **, 16 and Pi for j=O,..., 10. These calculations are enough to determine the number of eie'ments of each rank in the free distributive lattice on 5 generators a result first obtained by Church [2]. We also calculate the asymptotic behavior of the L,'s and Pj'S.
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