|کد مقاله||کد نشریه||سال انتشار||مقاله انگلیسی||ترجمه فارسی||نسخه تمام متن|
|4661597||1344846||2016||22 صفحه PDF||ندارد||دانلود رایگان|
The generic digraph (D,E)(D,E) is the unique countable homogeneous digraph that embeds all finite digraphs. In this paper, we determine the lattice of reducts of (D,E)(D,E), where a structure MM is a reduct of (D,E)(D,E) if it has domain D and all its ∅-definable relations are ∅-definable relations of (D,E)(D,E). As (D,E)(D,E) is ℵ0ℵ0-categorical, this is equivalent to determining the lattice of closed groups that lie in between Aut(D,E)Aut(D,E) and Sym(D)Sym(D).
Journal: Annals of Pure and Applied Logic - Volume 167, Issue 3, March 2016, Pages 370–391