Abstract
Let B be a 3-block of a finite group G with a defect group D. In this paper, we are mainly concerned with the number of characters in a particular block, so we shall use Isaacs’ approach to block structure. We consider the block B of a group G as a union of two sets, namely a set of irreducible ordinary characters of G having cardinality k(B) and a set of irreducible Brauer characters of G having cardinality l(B). We calculate k(B) and l(B) provided that D is normal in G and \(D \cong \left\langle {x,y,z|x^{3^n } = y^{3^m } = z^3 = \left[ {x,z} \right] = \left[ {y,z} \right] = 1,\left[ {x,y} \right] = z} \right\rangle \left( {n > m \geqslant 2} \right)\) .
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Acknowledgements
The authors are grateful to Prof. Jiping Zhang for his helpful suggestions and constructive criticism. Thanks are also given to the referee who made many valuable comments on this paper.
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Supported by National Natural Science Foundation of China (Grant No. 13101193); Zhejiang Natural Science Foundation (Grant No. LY16A010016)
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Yang, S., Gao, S. & Xu, C.B. On the number of irreducible characters in a 3-block with a minimal nonabelian defect group. Acta. Math. Sin.-English Ser. 33, 1267–1274 (2017). https://doi.org/10.1007/s10114-017-5792-4
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DOI: https://doi.org/10.1007/s10114-017-5792-4