منابع مشابه
Leafy Spanning
We prove that the d-dimensional hypercube, Hd, with n = 2 d vertices, contains a spanning tree with at least 1 ? 2 log 2 n ? o 1 log n n + 2 leaves. This improves upon the bound implied by a more general result on spanning trees in graphs with minimum degree , which gives 1 ? O(log log n) log 2 n n as a lower bound on the maximum number of leaves in spanning trees of n-vertex hypercubes.
متن کاملLeafy spanning trees in hypercubes
Given an undirected graph G V E the problem of nding a spanning tree T of G with the maximum number of leaves is NP Complete Constant factor approximation algorithms are known for this problem but the problem does not admit a polynomial time approximation scheme unless P NP Kleitman and West gave a lower bound of ln n on the function l n which is de ned as the minimum of the maximum number of l...
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The first step in flower development is the generation of a floral meristem by the inflorescence meristem. We have analyzed how this process is affected by mutant alleles of the Arabidopsis gene LEAFY. We show that LEAFY interacts with another floral control gene, APETALA1, to promote the transition from inflorescence to floral meristem. We have cloned the LEAFY gene, and, consistent with the m...
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ژورنال
عنوان ژورنال: Nature
سال: 1995
ISSN: 0028-0836,1476-4687
DOI: 10.1038/377482a0