Linear extensions and order-preserving poset partitions
نویسندگان
چکیده
منابع مشابه
Linear extensions and order-preserving poset partitions
We examine the lattice of all order congruences of a finite poset from the viewpoint of combinatorial algebraic topology. We will prove that the order complex of the lattice of all nontrivial order congruences (or order-preserving partitions) of a finite n-element poset P with n ≥ 3 is homotopy equivalent to a wedge of spheres of dimension n − 3. If P is connected, then the number of spheres is...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 2014
ISSN: 0097-3165
DOI: 10.1016/j.jcta.2013.09.010