Brauer's permutation lemma (source code)

= Brauer's permutation lemma
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A group of <automorphisms> of a <finite group> permutes both its <conjugacy classes> and its <irreducible characters>. The two <permutation representations> have the same <character>: each automorphism fixes equally many conjugacy classes and irreducible characters. The invertible <character table> intertwines the two permutation matrices, which have equal traces. The claim concerns fixed classes, not merely fixed elements.