Jerry Bryan asks:
... doesn't the center of GE (and of G) in fact consist
of more than just the Superflip and the identity? Does it
not also include the Pons Asinorum and the composition of
the Pons Asinorum and the Superflip?
Hmmm, I don't think so...
The centre commutes with every process, and the Pons Asinorum
E.g. R1 + F2 B2 U2 D2 L2 R2 <> F2 B2 U2 D2 L2 R2 + R1
I think Martin has scoped out all the possible centres in other
-> Mark <-