Divisible designs and semi-regular relative difference sets from additive Hadamard cocycles
نویسندگان
چکیده
منابع مشابه
A Note on New Semi-Regular Divisible Difference Sets
We give a C0051JUCtion for new families of semi-regular divisible difference sets. The construction iJ a variation of McFarland's scheme [Sl tor nonc;yclic difference SCIS. • Let G be a group of order 11111 and N a subgroup of G of order n. If D is a k-subset of G then Dis a {m, n, le , >.1, >.2) divisible difference set in G relative to N provided that the differences dd'1 fur d, d ' ED, d ;e ...
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We give two constructions for semi-regular relative difference sets (RDSs) in groups whose order is not a prime power, where the order u of the forbidden subgroup is greater than 2. No such RDSs were previously known. We use examples from the first construction to produce semi-regular RDSs in groups whose order can contain more than two distinct prime factors. For u greater than 2 these are the...
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Article history: Received 19 October 2007 Available online 16 April 2008 Communicated by Charles J. Colbourn
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For every positive integer m, we construct a symmetric (v, k, λ)-design with parameters v = h((2h−1) 2m−1) h−1 , k = h(2h − 1)2m−1, and λ = h(h − 1)(2h − 1)2m−2, where h = ±3 · 2 and |2h − 1| is a prime power. For m ≥ 2 and d ≥ 1, these parameter values were previously undecided. The tools used in the construction are balanced generalized weighing matrices and regular Hadamard matrices of order...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 2011
ISSN: 0097-3165
DOI: 10.1016/j.jcta.2011.04.016