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Counterexample bank

Part C is won by knowing which tempting claims are false. 148 counterexamples; 85 free. The rest come with the Notes pack.

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#1 · Complex Analysis, Algebra & Topology › Groups

“Aₙ is simple for every n ≥ 3” — false

Counterexample: A₄ has the normal subgroup V₄ = {e, (12)(34), (13)(24), (14)(23)}

groupspermutations