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On the growth problem for skew and symmetric conference matrices

✍ Scribed by C. Kravvaritis; M. Mitrouli; Jennifer Seberry


Publisher
Elsevier Science
Year
2005
Tongue
English
Weight
271 KB
Volume
403
Category
Article
ISSN
0024-3795

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✦ Synopsis


Koukouvinos et al.

[C. Koukouvinos, M. Mitrouli, J. Seberry, Growth in Gaussian elimination for weighing matrices, W (n, n -1), Linear Algebra Appl. 306 (2000) 189-202], conjectured that the growth factor for Gaussian elimination of any completely pivoted weighing matrix of order n and weight n -1 is n -1 and that the first and last few pivots are 1, 2, 2, 3 or 4, . . . , n -1 or n-1 2 , n-1 2 , n -1 for n > 14. In the present paper we study the growth problem for skew and symmetric conference matrices.

An algorithm for extending a k Γ— k matrix with elements 0, Β±1 to a skew and symmetric conference matrix of order n is described. By using this algorithm we show that the unique W (8, 7) has two pivot structures. We also prove that the unique W (10, 9) has three pivot patterns.


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