Title
Almost Optimal Cover-Free Families
Abstract
Roughly speaking, an (n, (r, s))-Cover Free Family (CFF) is a small set of n-bit strings such that: "in any d := r+s indices we see all patterns of weight r". CFFs have been of interest for a long time both in discrete mathematics as part of block design theory, and in theoretical computer science where they have found a variety of applications, for example, in parametrized algorithms where they were introduced in the recent breakthrough work of Fomin, Lokshtanov and Saurabh [16] under the name 'lopsided universal sets'. In this paper we give the first explicit construction of cover-free families of optimal size up to lower order multiplicative terms, for any r and s. In fact, our construction time is almost linear in the size of the family. Before our work, such a result existed only for r = d degrees((1)), and r = omega (d/(log log d log log log d)). As a sample application, we improve the running times of parameterized algorithms from the recent work of Gabizon, Lokshtanov and Pilipczuk [18].
Year
DOI
Venue
2015
10.1007/978-3-319-57586-5_13
ALGORITHMS AND COMPLEXITY (CIAC 2017)
Field
DocType
Volume
Discrete mathematics,Combinatorics,Parametrization,Multiplicative function,Block design,Omega,Small set,Mathematics,Parameterized algorithms,Universal set
Journal
10236
ISSN
Citations 
PageRank 
0302-9743
7
0.48
References 
Authors
24
2
Name
Order
Citations
PageRank
Nader H. Bshouty11171126.09
Ariel Gabizon215613.97