A question about Normal subgroups of $S_4$.
11731
Normal subgroups of $S_4$
22444
Normal subgroups of dihedral groups
70373
Intersection of normal subgroups proof
59138
Subgroups of $S_4$ isomorpic to $S_2$
99114
Subgroups of index 3 are normal
44934
Show that every normal subgroup can be written as an intersection of $\ker \chi$'s for $\chi \in \operatorname{Irr}(G).$
137691
What are the self-normalizing subgroups of $S_n$?
113357
Groups of order $pqr$ and their normal subgroups
13523
Are normal subgroups transitive?
12589
Show that every subgroup of the quaternion group Q is a normal subgroup of Q
89508
Existence of normal subgroups for a group of order $36$
45580
Intersection of conjugate subgroups is normal
63780
to show characteristic subgroup is normal in G
43651
Normal subgroups and factor groups
7973
Groups of order $pq$ have a proper normal subgroup
2174
Proving that HK is a subgroup when K is normal
61373
A normal subgroup that is not a characteristic