Some results on weighing matrices
نویسندگان
چکیده
منابع مشابه
Some New Results on Circulant Weighing Matrices
We obtain a few structural theorems for circulant weighing matrices whose weight is the square of a prime number. Our results provide new schemes to search for these objects. We also establish the existence status of several previously open cases of circulant weighing matrices. More specifically we show their nonexistence for the parameter pairs (n, k) (here n is the order of the matrix and k i...
متن کاملSome infinite classes of Williamson matrices and weighing matrices
Williamson type matrices A, B, C 1 D will be called nice if ABT + C DT = 0, perfect if ABT + CDT = ACT + BDT 0, special if ABT + CDT = ACT + BDT = ADT + BCT = o. Type 1 (1 , -1 )-matrices A, B, C, D of order n will be called tight Williamson-like matrices if AAT + BBT + CCT + DDT 4nIn and ABT + BAT + CDT + DCT o. Write N = 32T . piTl ••• p!Tn , where Pj 3(mod 4), Pj > 3, j = 1, ... ,n and r, rl...
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Algebraic techniques are employed to obtain necessary conditions for the existence of certain circulant weighing matrices. As an application we rule out the existence of many circulant weighing matrices. We study orders n = 8 +8+1, for 10 ~ 8 ~ 25. These orders correspond to the number of points in a projective plane of order 8.
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ژورنال
عنوان ژورنال: Bulletin of the Australian Mathematical Society
سال: 1975
ISSN: 0004-9727,1755-1633
DOI: 10.1017/s0004972700024096