Automorphism Groups of Partial Orders
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چکیده
1. The automorphism group T(P) of a partial order P is the collection of all order preserving permutations (automorphisms) of P, a subgroup of the symmetric group on P. If P and g are partial orders then P x g becomes a partial order by reverse lexicography: (p, q) < (p', q') if q < q' or q = q' and p < p'. If ƒ is a function whose domain contains the element a, we use af to denote the image of a under ƒ.
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