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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeDec 14th 2012

expanded E6 a bit.

• CommentRowNumber2.
• CommentAuthorDavid_Corfield
• CommentTimeDec 17th 2020

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.