Frank a Campo

activity

20182021

collaborators

8 papers

math.CO2021

A generalization of a theorem of Erné

Frank a Campo

Let $X$ be a finite set, $Z \subseteq X$ and $y \in / X$ . Marcel Erné showed in 1981, that the number of posets on $X$ containing $Z$ as an antichain equals the number of posets $…

math.CO2021

A recursive approach for the enumeration of the homomorphisms from a poset $P$ to the chain $C_{3}$

Frank a Campo

Let $H (P, C_{3})$ be the set of order homomorphisms from a poset $P$ to the chain $C_{3} = 1 < 2 < 3$ . We develop a recursive approach for the calculation of the cardinality of $…

math.CO2020

Criteria for the less-equal-relation between partial Lovász-vectors of digraphs

Frank a Campo

Finite digraphs $R$ and $S$ are studied with $# H (G, R) \leq # H (G, S)$ for every finite digraph $G \in D^{'}$ , where $H (G, H)$ is the set of order ho…

math.CO2020

Interdependencies of less-equal-relations between partial Lovász-vectors of digraphs

Frank a Campo

For digraphs $G$ and $H$ , let $H (G, H)$ be the set of all homomorphisms from $G$ to $H$ , and let $S (G, H)$ be the subset of those homomorphisms mapping all proper arcs…

math.CO2019

Strong G-schemes and strict homomorphisms

Frank a Campo

Let $P_{r}$ be a representation system of the non-isomorphic finite posets, and let $H (P, Q)$ be the set of order homomorphisms from $P$ to $Q$ . For finite posets $R…

math.CO2019

Calculation Rules and Cancellation Rules for Strong Hom-Schemes

Frank a Campo

Let $H (A, B)$ denote the set of homomorphisms from the poset $A$ to the poset $B$ . In previous studies, the author has started to analyze what it is in the structure of finit…

A generalization of a theorem of Erné

A recursive approach for the enumeration of the homomorphisms from a poset P to the chain C3​

Criteria for the less-equal-relation between partial Lovász-vectors of digraphs

Interdependencies of less-equal-relations between partial Lovász-vectors of digraphs

Strong G-schemes and strict homomorphisms

Calculation Rules and Cancellation Rules for Strong Hom-Schemes

A recursive approach for the enumeration of the homomorphisms from a poset $P$ to the chain $C_{3}$