What are the conjugacy classes of $(21)$ in $S_4$?
I think they are $\{(12),(13),(14),(23),(24),(34)\}$
But I'm not sure and the centralizer of $(12)$ is $\{(21),(34)\}$. Is this right?
What are the conjugacy classes of $(21)$ in $S_4$?
I think they are $\{(12),(13),(14),(23),(24),(34)\}$
But I'm not sure and the centralizer of $(12)$ is $\{(21),(34)\}$. Is this right?
Copyright © 2021 JogjaFile Inc.
Conjugation of permutations preserves cycle type, so, yes, the conjugacy class is correct.
Note that the identity is in the centraliser too. It is also closed (as it is a subgroup of $S_4$), so the product $(12)(34)$ is in there as well.