Beltrán, Antonio; Felipe Román, María Josefa; SHAO, CHANG GUO(World Scientific Publishing, 2012-12)
The authors have realized that in the proof of Theorem 6 of [1] there is a mistake
although the conclusion of the theorem is correct. The proof of the theorem is
divided into two cases: when there exist no p-elements of ...
Alemany Martínez, Elena; Beltrán, Antonio; Felipe Román, María Josefa(Cambridge University Press, 2012)
Let G be a finite p-solvable group. We prove that if G has exactly two conjugacy class sizes of p'-elements of prime power order, say 1 and m, then m = p(a)q(b), for two distinct primes p and q, and G either has an abelian ...
Beltrán, Antonio; Felipe Román, María Josefa(World Scientific Publishing, 2012-04)
It is shown that if the set of conjugacy class sizes of a finite group G is {1,m,n,mn}, where m, n are positive integers which do not divide each other, then G is up to central factors a {p,q}-group. In particular, G is solvable.
Beltrán, Antonio; Felipe Román, María Josefa(Debreceni egyetem matematika intézet, 2013)
[EN] We study the solvability of a normal subgroup N of a finite group G having exactly three G-conjugacy class sizes. We show that if the set of G-class sizes of N is {1, m, mpa
}, with p a prime not dividing m, then N ...