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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.
expanded E6 a bit.
Added this fact mentioned by John Baez here:
The Dynkin diagram of $E_6$ has 2-fold symmetry, corresponding to a outer automorphism of order 2. $E_6$ acts on the octonionic projective plane and its nontrivial outer automorphism gives rise to a projective duality in its geometry.
1 to 2 of 2