Minimal generating set of Sylow 2-subgroups commutator subgroup of alternating group. Commutator width in Sylow $p$-subgroups of alternating, symmetric groups and in the wreath product of groups

Abstract

The size of minimal generating set for commutator of Sylow 2-subgroup of alternating group was found. Given a permutational wreath product of finite cyclic groups sequence we prove that the commutator width of such groups is 1 and we research some properties of its commutator subgroup. It was shown that $(Syl_2 A_{2^k})^2 = Syl'_2 (A_{2^k}), \, k>2$. A new approach to presentation of Sylow 2-subgroups of alternating group ${A_{{2^{k}}}}$ was applied. As a result the short proof that the commutator width of Sylow 2-subgroups of alternating group ${A_{{2^{k}}}}$, permutation group ${S_{{2^{k}}}}$ and Sylow $p$-subgroups of $Syl_2 A_{p^k}$ ($Syl_2 S_{p^k}$) are equal to 1 was obtained. Commutator width of permutational wreath product $B \wr C_n$ were investigated. It was proven that the commutator length of an arbitrary element of commutator of the wreath product of cyclic groups $C_{p_i}, \, p_i\in \mathbb{N} $ equals to 1. The commutator width of direct limit of wreath product of cyclic groups are found. As a corollary, it was shown that the commutator width of Sylows $p$-subgroups $Syl_2(S_{{p^{k}}})$ of symmetric $S_{{p^{k}}}$ and alternating groups $A_{{p^{k}}}$ $p \geq 2$ are also equal to 1. A recursive presentation of Sylows $2$-subgroups $Syl_2(A_{{2^{k}}})$ of $A_{{2^{k}}}$ was introduced. The structure of Sylows $2$-subgroups commutator of symmetric and alternating groups were investigated. For an arbitrary group $B$ an upper bound of commutator width of $C_p \wr B$ was founded.