We find an explicit formula for the number of graded partially ordered sets of rank h that can be defined on a set containing n elements. Also, we find the number of graded partially ordered sets of length h, and having a greatest and least element that can be defined on a set containing n elements. The first result provides a lower bound for G*(n), the number of posets that can be defined on an n-set; the second result provides an upper bound for the number of lattices satisfying the Jordan-Dedekind chain condition that can be defined on an n-set
AbstractIn this paper, we show that if a partially ordered set has 2n elements and has dimension n, ...
AbstractWe consider the problem of determining which partially ordered sets on n points with k pairs...
Given a set of permutations ∑,Sn⊇∑, a poset P = P(∑) is chain-permutational with respect to ∑ if it ...
We find an explicit formula for the number of graded partially ordered sets of rank h that can be de...
AbstractWe find an explicit formula for the number of graded partially ordered sets of rank h that c...
AbstractThis note is a continuation of [2]; we describe here how to enumerate classes of isomorphic ...
A semiorder is a partially ordered set P with two certain forbidden induced sub-posets. This paper e...
Kleitman and Rothschild (Trans. Amer. Math. Soc. 205 (1975), 205–220) gave an asymptotic formula for...
We introduce the distinguishing numbers of partially ordered sets. This study has given us the oppor...
AbstractThe dimension of a partially ordered set P is the smallest integer n (if it exists) such tha...
AbstractWe present some combinatorial identities concerning the number T0(n,j) of all T0 topologies ...
The upper class of a lattice rule is a convenient entity for classification and other purposes. The ...
AbstractIt is well known that the linear extension majority relation of a partially ordered set (P,≤...
AbstractFix an element x of a finite partially ordered set P on n elements. Then let hi(x) be the nu...
AbstractWe define a ‘tiered poset’ N of cardinality n by the condition that all the maximal chains h...
AbstractIn this paper, we show that if a partially ordered set has 2n elements and has dimension n, ...
AbstractWe consider the problem of determining which partially ordered sets on n points with k pairs...
Given a set of permutations ∑,Sn⊇∑, a poset P = P(∑) is chain-permutational with respect to ∑ if it ...
We find an explicit formula for the number of graded partially ordered sets of rank h that can be de...
AbstractWe find an explicit formula for the number of graded partially ordered sets of rank h that c...
AbstractThis note is a continuation of [2]; we describe here how to enumerate classes of isomorphic ...
A semiorder is a partially ordered set P with two certain forbidden induced sub-posets. This paper e...
Kleitman and Rothschild (Trans. Amer. Math. Soc. 205 (1975), 205–220) gave an asymptotic formula for...
We introduce the distinguishing numbers of partially ordered sets. This study has given us the oppor...
AbstractThe dimension of a partially ordered set P is the smallest integer n (if it exists) such tha...
AbstractWe present some combinatorial identities concerning the number T0(n,j) of all T0 topologies ...
The upper class of a lattice rule is a convenient entity for classification and other purposes. The ...
AbstractIt is well known that the linear extension majority relation of a partially ordered set (P,≤...
AbstractFix an element x of a finite partially ordered set P on n elements. Then let hi(x) be the nu...
AbstractWe define a ‘tiered poset’ N of cardinality n by the condition that all the maximal chains h...
AbstractIn this paper, we show that if a partially ordered set has 2n elements and has dimension n, ...
AbstractWe consider the problem of determining which partially ordered sets on n points with k pairs...
Given a set of permutations ∑,Sn⊇∑, a poset P = P(∑) is chain-permutational with respect to ∑ if it ...