Non-normal Klein four-subgroups of symmetric group:S4

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This article is about a particular subgroup in a group, up to equivalence of subgroups (i.e., an isomorphism of groups that induces the corresponding isomorphism of subgroups). The subgroup is (up to isomorphism) Klein four-group and the group is (up to isomorphism) symmetric group:S4 (see subgroup structure of symmetric group:S4).
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We consider the subgroup in the group defined as follows.

is the symmetric group of degree four, which for concreteness we take as the symmetric group on the set .

is the Young subgroup for the partition . Explicitly, it is the subgroup comprising those permutations that send each of the subsets and to within itself. has a total of three conjugates, listed below:

Our local name Partition stabilized Set of all elements in the stabilizing subgroup

(and hence each of its conjugate subgroups) is isomorphic to the Klein four-group. However, has another subgroup isomorphic to the Klein four-group that is not one of these conjugate subgroups, and is not automorphic to these either. That is the normal Klein four-subgroup of symmetric group:S4 that comprises the identity element and the three double transpositions. The current article is not about that subgroup.