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
I'm trying to prove that the group below isn't cyclic:
$G = \{ (1, 2, 3, ... n)^a\cdot(n+1, n+2, n+3, ... 2n)^b \mid 0 \leq a,b \leq n-1 \}$
To do this, I'm trying to show that none of the elements of $G$ have order $n^2$ - however I've made little progress.
Any help would be much appreciated,...