Published online by Cambridge University Press: 22 January 2016
In [1] R. Brauer asked the following question: Let be a finite group, p a rational prime number, and B a p-block of
with defect d and defect group
. Is it true that
is abelian if and only if every irreducible character in B has height 0 ? The present results on this problem are quite incomplete. If d-0, 1, 2 the conjecture was proved by Brauer and Feit, [4] Theorem 2. They also showed that if
is cyclic, then no characters of positive height appear in B. If
is normal in
, the conjecture was proved by W. Reynolds and M. Suzuki, [12]. In this paper we shall show that for a solvable group
, the conjecture is true for the largest prime divisor p of the order of
. Actually, one half of this has already been proved in [7]. There it was shown that if
is a p-solvable group, where p is any prime, and if
is abelian, then the condition on the irreducible characters in B is satisfied.