A small dual-automorphic lattice with no involutory dual automorphism
نویسندگان
چکیده
An exercise in Garrett Birkhoff’s renowned book on lattice theory asks for a lattice with 18 elements and of length 5 that has a dual automorphism, but no involutory dual automorphism. This note constructs a smaller lattice, 15 elements and length 4, with the same property.
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