DM
2011
12 years 8 months ago
2011
A relational first order structure is homogeneous if it is countable (possibly finite) and every isomorphism between finite substructures extends to an automorphism. This artic...
JSC
2010
13 years 3 months ago
2010
We examine designs and binary codes associated with the line graph of the n-cube Qn, i.e. the Hamming graph H(n, 2). We find the automorphism groups and the parameters of the cod...
ORDER
2000
13 years 4 months ago
2000
We prove that, given a nontrivial Boolean algebra B, a compact convex set S and a group G, there is an orthomodular lattice L with the center isomorphic to B, the automorphism grou...
COMBINATORICS
2000
13 years 4 months ago
2000
Two tournaments T1 and T2 on the same vertex set X are said to be switching equivalent if X has a subset Y such that T2 arises from T1 by switching all arcs between Y and its comp...
IJAC
2007
13 years 4 months ago
2007
We show that certain finite groups do not arise as the automorphism group of the square of a finite algebraic structure, nor as the automorphism group of a finite, 2-generated, ...
GC
2007
Springer
13 years 4 months ago
2007
Springer
Let Γ be a finite digraph and let G be a subgroup of the automorphism group of Γ. A directed cycle C of Γ is called G-consistent whenever there is an element of G whose restri...
EJC
2007
13 years 4 months ago
2007
We present a new family of locally 5–arc transitive graphs. The graphs constructed are bipartite with valency {2m + 1, 2m}. The actions of the automorphism group on the two bipa...
JCT
2006
13 years 4 months ago
2006
A Latin square design whose automorphism group is transitive of rank at most 3 on points must come from the multiplication table of an elementary abelian p-group, for some prime p...
DM
2007
13 years 4 months ago
2007
We investigate the existence of 3-designs and uniform large sets of 3-designs with block size 6 admitting PSL(2, q) as an automorphism group. We show the existence of simple 3-(28...
COMBINATORICS
2007
13 years 4 months ago
2007
A hypermap is (hypervertex-) bipartite if its hypervertices can be 2-coloured in such a way that “neighbouring” hypervertices have different colours. It is bipartiteuniform i...