A new series of dense graphs of high girth
F Lazebnik, VA Ustimenko, AJ Woldar - Bulletin of the American …, 1995 - ams.org
Let $ k\geq 1$ be an odd integer, ${t=\left\lfloor {\tfrac {{k+ 2}}{4}}\right\rfloor} $, and q be a
prime power. We construct a bipartite, q-regular, edge-transitive graph $ CD (k, q) $ of order $\…
prime power. We construct a bipartite, q-regular, edge-transitive graph $ CD (k, q) $ of order $\…
Simple groups are characterized by their non-commuting graphs
RM Solomon, AJ Woldar - Journal of Group Theory, 2013 - degruyter.com
The non-commuting graph of a finite group G is a highly symmetrical object (indeed, embeds
in ), yet its complexity pales in comparison to that of G. Still, it is natural to seek conditions …
in ), yet its complexity pales in comparison to that of G. Still, it is natural to seek conditions …
On Hurwitz generation and genus actions of sporadic groups
AJ Woldar - Illinois Journal of Mathematics, 1989 - projecteuclid.org
Let S denote an orientablesurface of least genus on which the finite group G acts in an
effective and orientation-preserving manner. We define the genus g (G) of the group G to bethe …
effective and orientation-preserving manner. We define the genus g (G) of the group G to bethe …
A characterization of the components of the graphs D (k, q)
F Lazebnik, VA Ustimenko, AJ Woldar - Discrete Mathematics, 1996 - Elsevier
We study the graphs D(k,q) of [4] with particular emphasis on their connected components
when q is odd. In [6] the authors proved that these components (most often) provide the best-…
when q is odd. In [6] the authors proved that these components (most often) provide the best-…
[PDF][PDF] Sporadic simple groups which are Hurwitz
AJ Woldar - Journal of Algebra, 1991 - researchgate.net
In [lo] the author determines which sporadic groups other than Fizz, Fz3, Fb4, Th, J4, B, and
M are Hurwitz groups, ie, generated by elements x and y with order (x)= 2, order (y)= 3, and …
M are Hurwitz groups, ie, generated by elements x and y with order (x)= 2, order (y)= 3, and …
Polarities and 2k-cycle-free graphs
F Lazebnik, VA Ustimenko, AJ Woldar - Discrete Mathematics, 1999 - Elsevier
Let C 2k be the cycle on 2k vertices, and let ex(v, C 2k ) denote the greatest number of edges
in a simple graph on v vertices which contains no subgraph isomorphic to C 2k . In this …
in a simple graph on v vertices which contains no subgraph isomorphic to C 2k . In this …
3/2—Generation of the sporadic simple groups
AJ Woldar - Communications in algebra, 1994 - Taylor & Francis
A group G is said to be 3/2-generated if, given an arbitrary non-identity element x of G one
can always find an element y= y (x) of G such that (x, y)= G. We refer to such an element y as …
can always find an element y= y (x) of G such that (x, y)= G. We refer to such an element y as …
Upper bounds on the order of cages
…, VA Ustimenko, AJ Woldar - the electronic journal of …, 1997 - combinatorics.org
… In [12], Lazebnik, Ustimenko and Woldar showed that the graphs D(n, q) are disconnected
for n … , bi0j0 v2i0 , as otherwise K would be a cycle in either C or Hij for some i, j. But now the …
for n … , bi0j0 v2i0 , as otherwise K would be a cycle in either C or Hij for some i, j. But now the …
General properties of some families of graphs defined by systems of equations
F Lazebnik, AJ Woldar - Journal of Graph Theory, 2001 - Wiley Online Library
In this paper we present a simple method for constructing infinite families of graphs defined
by a class of systems of equations over commutative rings. We show that the graphs in all …
by a class of systems of equations over commutative rings. We show that the graphs in all …
A reduction theorem on purely singular splittings of cyclic groups
AJ Woldar - Proceedings of the American Mathematical Society, 1995 - ams.org
A set M of nonzero integers is said to split a finite abelian group G if there is a subset S of G
for which $ M\cdot S= G\backslash\{0\} $. If, moreover, each prime divisor of $| G| $ divides an …
for which $ M\cdot S= G\backslash\{0\} $. If, moreover, each prime divisor of $| G| $ divides an …