2018/01/16 by Júlia Kulin, Kulin, J\' ulia, Claudia Mureșan +1
Computer Science · Mathematics · #06B05 #06B10 #Advanced Algebra and Logic #Advanced Mathematical Identities #FOS: Mathematics #Rings and Algebras (math.RA) #Rough Sets and Fuzzy Logic
paper · pdf · doi:10.48550/arxiv.1801.05282
openalex publication_date 2018/01/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the smallest, as well as the largest numbers of congruences of lattices of an arbitrary finite cardinality n. Continuing the work of Freese and Cz' edli, we prove that the third, fourth and fifth largest numbers of congruences of an n--element lattice are: 5⋅ 2n-5 if n≥ 5, respectively 2n-3 and 7⋅ 2n-6 if n≥ 6. We also determine the structures of the n--element lattices having 5⋅ 2n-5, respectively 2n-3 congruences, along with the structures of their congruence lattices.