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arXiv · 1812.11512

A note on lattices with many sublattices

Gábor Czédli·Eszter K. Horváth
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Abstract

For every natural number $n\geq 5$, we prove that the number of subuniverses of an $n$-element lattice is $2^n$, $13\cdot 2^{n-4}$, $23\cdot 2^{n-5}$, or less than $23\cdot 2^{n-5}$. By a subuniverse, we mean a sublattice or the emptyset. Also, we describe the $n$-element lattices with exactly $2^n$, $13\cdot 2^{n-4}$, or $23\cdot 2^{n-5}$ subuniverses.

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Gábor Czédli, Eszter K. Horváth. 2018-12-30. A note on lattices with many sublattices. https://arxiv.org/abs/1812.11512

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