At least 2 errors appeared in my previous message:
In Minh Thai's 3-cycle, substitute "r" for "f" to do the permutation
reported.
In the Frye 3-cycle, the first "d" should be "d'".

>I thought I had a half center move:

(r2 u2)2  =  (Fur,Bur)

but when repeated, I got

(r2 u2)4  =  (Fdr,Bur),

>so I realized that what I really had was the 6-cycle of centers:

(r2 u2)2  = (Ful,Fdr,Bul,Bdl,Fur,Bur)   (I think).

Oh, well.

----   Stan
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