A note on “automorphism groups of partial orders”
نویسندگان
چکیده
منابع مشابه
Automorphism Groups of Partial Orders
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...
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1. Abstract A classiication was given in 1, 12, 13] of all the countable k-CS-transitive cycle-free partial orders for k 3. Here the elementary theories of these structures and their automorphism groups are examined, and it is shown that in many cases we can distinguish the structures or their groups by means of their rst or second order properties. The small index property is established for w...
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Results of the computation of the automorphism groups for the groups of orders 16p and 16p are given. In some cases it has not been possible to give as complete a set of results as was done previously for the case of groups of order 8p. Problems arise for those groups of the form (Cp×Cp) @ G[16] that occur in the orders p ≡ 1 mod(8) and p ≡ 7 mod(8), where G[16] means any group of order 16. The...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1978
ISSN: 0012-365X
DOI: 10.1016/0012-365x(78)90065-1