Abstract
In representation theory of finite groups, one of the most important and interesting problems is that, for a p-block A of a finite group G where p is a prime, the numbers k(A) and ℓ(A) of irreducible ordinary and Brauer characters, respectively, of G in A are p-locally determined. We calculate k(A) and ℓ(A) for the cases where A is a full defect p-block of G, namely, a defect group P of A is a Sylow p-subgroup of G and P is a nonabelian metacyclic p-group M n+1(p) of order p n+1 and exponent p n for \({n \geqslant 2}\), and where A is not necessarily a full defect p-block but its defect group P = M n+1(p) is normal in G. The proof is independent of the classification of finite simple groups.
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Holloway, M., Koshitani, S. & Kunugi, N. Blocks with nonabelian defect groups which have cyclic subgroups of index p . Arch. Math. 94, 101–116 (2010). https://doi.org/10.1007/s00013-009-0075-7
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DOI: https://doi.org/10.1007/s00013-009-0075-7