Let be a finite group and
be the set of all irreducible complex character degrees of
counting multiplicities.
Let be an odd prime number and M = PGL(2,p), M = Z2xPSL(2,p) or
. In this paper we prove that
is uniquely determined by its order and some information on its character degrees.
As a consequence of our results we prove that if
is a finite group such that
, then
. This implies that
is uniquely determined by the structure of its complex group algebra.
Key Words: Character degrees, order, projective special linear group, characterization
2010 Mathematics Subject Classification: Primary 20C15
Secondary 20D05, 20D60