Search Results - "Hilton, A.J.W."
-
1
Hall's theorem and extending partial latinized rectangles
Published in Journal of combinatorial theory. Series A (01-02-2015)“…We generalize a theorem of M. Hall Jr., that an r×n Latin rectangle on n symbols can be extended to an n×n Latin square on the same n symbols. Let p, n,…”
Get full text
Journal Article -
2
Degree-bounded factorizations of bipartite multigraphs and of pseudographs
Published in Discrete mathematics (28-01-2010)“…For d ≥ 1 , s ≥ 0 a ( d , d + s ) - graph is a graph whose degrees all lie in the interval { d , d + 1 , … , d + s } . For r ≥ 1 , a ≥ 0 an ( r , r + a ) -…”
Get full text
Journal Article Conference Proceeding -
3
A generalization of Talbot's theorem about King Arthur and his Knights of the Round Table
Published in Journal of combinatorial theory. Series A (01-07-2009)“…Let G be a graph consisting of powers of disjoint cycles and let A be an intersecting family of independent r-sets of vertices. Provided that G satisfies a…”
Get full text
Journal Article -
4
( r , r + 1 ) -factorizations of ( d , d + 1 ) -graphs
Published in Discrete mathematics (28-03-2008)“…A ( d , d + 1 ) -graph is a graph whose vertices all have degrees in the set { d , d + 1 } . Such a graph is semiregular. An ( r , r + 1 ) -factorization of a…”
Get full text
Journal Article Conference Proceeding -
5
Amalgamations of factorizations of complete equipartite graphs
Published in Discrete mathematics (06-07-2004)“…Let t be a positive integer, and let L=( l 1,…, l t ) and K=( k 1,…, k t ) be collections of nonnegative integers. A graph has a ( t, K, L) factorization if it…”
Get full text
Journal Article -
6
Amalgamations of connected k-factorizations
Published in Journal of combinatorial theory. Series B (01-07-2003)“…In this paper, necessary and sufficient conditions are found for a graph with exactly one amalgamated vertex to be the amalgamation of a k-factorization of K…”
Get full text
Journal Article -
7
Relations among the fractional chromatic, choice, Hall, and Hall-condition numbers of simple graphs
Published in Discrete mathematics (28-10-2001)“…Hall's condition for the existence of a proper vertex list-multicoloring of a simple graph G has recently been used to define the fractional Hall and…”
Get full text
Journal Article -
8
Aspects of edge list-colourings
Published in Discrete mathematics (28-03-2001)“…An assignment of colours to the edges of a multigraph is called an s -improper edge-colouring if no colour appears on more than s edges incident with any given…”
Get full text
Journal Article -
9
The Overfull Conjecture and the Conformability Conjecture
Published in Discrete mathematics (28-10-2001)“…In this paper we show that under some fairly general conditions the Overfull Conjecture about the chromatic index of a graph G implies the Conformability…”
Get full text
Journal Article -
10
Hamiltonian double latin squares
Published in Journal of combinatorial theory. Series B (2003)“…A double latin square of order 2 n on symbols σ 1,…, σ n is a 2 n×2 n matrix A=( a ij ) in which each a ij is one of the symbols σ 1,…, σ n and each σ k occurs…”
Get full text
Journal Article -
11
Non-conformable subgraphs of non-conformable graphs
Published in Discrete mathematics (28-09-2002)“…We show that if G and H are non-conformable graphs, with H being a subgraph of G of the same maximum degree Δ( G), and if Δ(G)⩾⌈ 1 2 |V(G)|⌉ , then | V( H)|=|…”
Get full text
Journal Article -
12
The structure of totally critical graphs of odd order
Published in Discrete mathematics (06-05-2003)“…It has been known for some time that if the Conformability Conjecture is true, then we can say exactly which graphs G of maximum degree Δ(G)⩾ 1 2 |V(G)| and…”
Get full text
Journal Article Conference Proceeding -
13
At most k-to-1 mappings between graphs, II
Published in Discrete mathematics (15-06-1996)“…Suppose that f is a (⩽ k)-to-1 function from a vertex set of a graph G onto a vertex set of a graph H. We ask when f extends to a continuous (⩽ k)-to-1 map…”
Get full text
Journal Article -
14
The Hall number, the Hall index, and the total Hall number of a graph
Published in Discrete Applied Mathematics (15-05-1999)“…We discuss the relationship between the Hall number of a graph and other well-known graph parameters, including the choice number and the chromatic number. We…”
Get full text
Journal Article Conference Proceeding -
15
Vertex-splitting and chromatic index critical graphs
Published in Discrete Applied Mathematics (13-06-1997)“…We study graphs which are critical with respect to the chromatic index. We relate these to the Overfull Conjecture and we study in particular their…”
Get full text
Journal Article -
16
Fractional latin squares, simplex algebras, and generalized quotients
Published in Journal of statistical planning and inference (01-05-2000)“…Recently the authors defined the concept of a weighted quasigroup, and showed that each weighted quasigroup is the amalgamation of a quasigroup. Similar…”
Get full text
Journal Article -
17
A Vertex-Splitting Lemma, de Werra's Theorem, and Improper List Colourings
Published in Journal of combinatorial theory. Series B (01-01-1998)“…We prove a new vertex-splitting lemma which states that if a multigraphGhas maximum multiplicity of at mostp, then each vertex u can be split into ⌈(d(u)/p)⌉…”
Get full text
Journal Article -
18
Triangulations of 3-way regular tripartite graphs of degree 4, with applications to orthogonal latin squares
Published in Discrete mathematics (15-04-1997)“…If G is a regular tripartite graph of degree d( G) with tripartition ( A, B, C) of V( G) such that the bipartite subgraphs induced by each of A ∪ B, B ∪ C, C ∪…”
Get full text
Journal Article -
19
Totally Critical Even Order Graphs
Published in Journal of combinatorial theory. Series B (01-07-1999)“…A graph is totally critical if it is Type 2, connected, and the removal of any edge reduces the total chromatic number. A good characterization of all totally…”
Get full text
Journal Article -
20
Graphs that admit 3-to-1 or 2-to-1 maps onto the circle
Published in Discrete Applied Mathematics (07-03-1996)“…We give a complete and explicit characterization of the connected graphs which admit a continuous 3-to-l map onto the circle, and of the connected graphs which…”
Get full text
Journal Article