40 Is $n! + 1$ often a prime? 33 A group with five elements is Abelian 19 System of nonlinear equations that leads to cubic equation 14 Abelian Group Not Finitely Generated 13 Is it true that an element of a group whose order divides the order a subgroup is an element of the subgroup

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 +20 Let $G$ be a group, and $H \le G$. For what pairs $(G,H)$ is $Z(H)=Z(G)\cap H$ true? +10 Probabilistic Interpretation of Burnside's Lemma +10 If $G'/G''$ and $G''/G'''$ are cyclic, then $G''=1$ +10 Prove that a group $G$ of order 280 is not simple and has a subgroup of order 35

Questions (18)

 196 How can a piece of A4 paper be folded in exactly three equal parts? 16 Generalization of index 2 subgroups are normal 15 Subrings of finite index and units 13 Applications of the fact that a group is never the union of two of its proper subgroups 12 Finite groups of which the centralizer of each element is normal.

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