Sunflowers in Lattices
نویسندگان
چکیده
منابع مشابه
Sunflowers in Lattices
A Sunflower is a subset S of a lattice, with the property that the meet of any two elements in S coincides with the meet of all of S. The Sunflower Lemma of Erdös and Rado [2] asserts that a set of size at least 1 + k!(t − 1)k of elements of rank k in a Boolean Lattice contains a sunflower of size t. We develop counterparts of the Sunflower Lemma for distributive lattices, graphic matroids, and...
متن کاملRegularity in residuated lattices
In this paper, we study residuated lattices in order to give new characterizations for dense, regular and Boolean elements in residuated lattices and investigate special residuated lattices in order to obtain new characterizations for the directly indecomposable subvariety of Stonean residuated lattices. Free algebra in varieties of Stonean residuated lattices is constructed. We introduce in re...
متن کاملRapid hybrid speciation in wild sunflowers.
Hybrid or "recombinational" speciation refers to the origin of a new homoploid species via hybridization between chromosomally or genetically divergent parental species. Theory predicts that this mode of speciation is punctuated, but there has been little empirical evidence to support this claim. Here, we test the hypothesis of rapid hybrid speciation by estimating the sizes of parental species...
متن کاملAn equivalence functor between local vector lattices and vector lattices
We call a local vector lattice any vector lattice with a distinguished positive strong unit and having exactly one maximal ideal (its radical). We provide a short study of local vector lattices. In this regards, some characterizations of local vector lattices are given. For instance, we prove that a vector lattice with a distinguished strong unit is local if and only if it is clean with non no-...
متن کاملWilliam Pickles lecture 1989. Seeing sunflowers.
THE clearest memory I have from my first year as a medical student is of a botany practical. We had the task, one sunny Thursday afternoon, of cutting a very thin slice of a sunflower stem, putting it under the microscope and drawing what we saw. In the textbook there was an illustration of what we should expect to see: as I remember, it showed regular, neatly-'packed cells with several smaller...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Electronic Journal of Combinatorics
سال: 2005
ISSN: 1077-8926
DOI: 10.37236/1963