Abstract
We present some important general methods which allow to bound the number of characters in a given block of a finite group provided local information is available. Most results are stated in terms of Cartan invariants of subsections. We also provide a practical algorithm for computing Cartan invariants up to basic sets. This algorithm will be used in the following chapters.
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Sambale, B. (2014). The Cartan Method. In: Blocks of Finite Groups and Their Invariants. Lecture Notes in Mathematics, vol 2127. Springer, Cham. https://doi.org/10.1007/978-3-319-12006-5_4
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DOI: https://doi.org/10.1007/978-3-319-12006-5_4
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