Covering arrays with mixed alphabet sizes
Lucia Moura, John Stardom, Brett Stevens, Alan W. Williams · Journal of Combinatorial Designs · 2003
Abstract Covering arrays with mixed alphabet sizes, or simplymixed covering arrays, are natural generalizations of covering arrays that are motivated by applications in software and network testing. A (mixed) covering arrayAof type$\prod _{i=1}^{k}g_i$ is ak×Narray with the cells of rowifilled with elements from ℤ and having the property that for every two rowsiandjand every ordered pair of elements (e,f) ∈ ℤ × ℤ , there exists at least one columnc, 1 ≤ c ≤ N, such thatAi,c = eandAj,c = f. The (mixed) covering array number, denoted by$ca(\prod _{i=1}^{k}g_i)$ , is the minimumNfor which a covering array of type$\prod _{i=1}^{k}g_i$ withNcolumns exists. In this paper, several constructions for mixed covering arrays are presented, and the mixed covering array numbers are determined for nearly all cases withk = 4 and for a number of cases withk = 5. © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 413–432, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10059