A simple graph G=(V,E) is said to be antimagic if there exists a bijection f:E¿[1,|E|] such that the sum of the values of f on edges incident to a vertex takes different values on distinct vertices. The graph G is distance ...

Aquest text conté una introducció a l’àlgebra lineal com a eina imprescindible per a la resolució de sistemes lineals. Aquest problema es planteja tant per a sistemes consistents com per a aquells sistemes que no tenen ...

An old conjecture of Ringel states that every tree with m edges decomposes the complete graph K2m+1. The best known lower bound for the order of a complete graph which admits a decomposition by every given tree with m edges ...

An old conjecture of Ringel states that every tree with m edges decom- poses the complete graph K 2 m +1 . A more general version of the Ringel’s conjecture says that every tree with m edges decomposes K rm +1 for each r ...

The Ascending Subgraph Decomposition (ASD) Conjecture asserts that every graph G with (n+12) edges admits an edge decomposition G=H1¿¿¿Hn such that Hi has i edges and it is isomorphic to a subgraph of Hi+1, i=1,…,n-1. We ...

The Ascending Subgraph Decomposition (ASD) Conjecture asserts that every graph G with View the MathML source(n+12) edges admits an edge decomposition G=H1¿¿¿HnG=H1¿¿¿Hn such that HiHi has i edges and is isomorphic to ...

Sea X un conjunto de n enteros y M = {m1 ≥ · · · ≥ mk} una secuencia de enteros positivos. El problema consiste en encontrar una partici´on de X en k subconjuntos mutuamente disjuntos X1, . . . ,Xk tal que la suma de los ...

The following problem arises in the design of some interconnection networks for distributed systems. Namely, to construct digraphs with given maximum out-degree, reduced diameter, easy routing, good connectivity, and ...

A d-regular graph is said to be superconnected if any disconnecting subset with cardinality at most d is formed by the neighbors of some vertex. A superconnected graph that remains connected after the failure of a vertex ...