Blocking numbers and fixing numbers of convex bodies
نویسندگان
چکیده
منابع مشابه
Fixing Numbers for Matroids
Motivated by work in graph theory, we define the fixing number for a matroid. We give upper and lower bounds for fixing numbers for a general matroid in terms of the size and maximum orbit size (under the action of the matroid automorphism group). We prove the fixing numbers for the cycle matroid and bicircular matroid associated with 3-connected graphs are identical. Many of these results have...
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L. Fejes Tóth [1] introduced the notion of fixing system for a compact, convex body M ⊂ Rn. Such a system F ⊂ bd M stabilizes M with respect to translations. In particular, every minimal fixing system F is primitive, i.e., no proper subset of F is a fixing system. In [2] lower and upper bounds for cardinalities of mimimal fixing systems are indicated. Here we give an improved lower bound and sh...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2009
ISSN: 0012-365X
DOI: 10.1016/j.disc.2009.06.034