Article ID Journal Published Year Pages File Type
1150014 Journal of Statistical Planning and Inference 2008 8 Pages PDF
Abstract
Two matrices with elements taken from the set {-1,1} are Hadamard equivalent if one can be converted into the other by a sequence of permutations of rows and columns, and negations of rows and columns. In this paper we summarize what is known about the number of equivalence classes of matrices having maximal determinant. We establish that there are 7 equivalence classes for matrices of order 21 and that there are at least 9884 equivalence classes for matrices of order 26. The latter result is obtained primarily using a switching technique for producing new designs from old.
Related Topics
Physical Sciences and Engineering Mathematics Applied Mathematics
Authors
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