Binzhou Xia

BERNOULLI NUMBERS AND CONGRUENCES FOR HARMONIC SUMS

Zhao established the following harmonic congruence for prime p > 3: In this note, the authors improve it to the following congruence for prime p > 5: Meanwhile, they also improve a generalization of Zhaos congruence and extend Eisensteins congruence.

Perfect Codes in Cayley Graphs

Given a graph

Cyclotomic difference sets in finite fields

\Gamma

Vertex-quasiprimitive 2-arc-transitive digraphs

, a subset

Cubic graphical regular representations of PSL 2 ( q )

C

Stability of circulant graphs

of

An infinite family of cubic nonnormal Cayley graphs on nonabelian simple groups

V(\Gamma)

An infinite family of vertex-primitive 2-arc-transitive digraphs

is called a perfect code in

Vertex-imprimitive symmetric graphs with exactly one edge between any two distinct blocks

\Gamma

The covering radius of PGL2(q)

if every vertex of