Block Intersection Numbers of Block Designs Ii
نویسندگان
چکیده
منابع مشابه
Quasi-symmetric 3-designs with a fixed block intersection number
Quasi-symmetric 3-designs with block intersection numbers x, y (0 ≤ x ≤ y < k) are studied. It is proved that the parameter λ of a quasi-symmetric 3-(v, k, λ) design satisfies a quadratic whose coefficients are polynomial functions of k, x and y. We use this quadratic to prove that there exist finitely many quasi-symmetric 3-designs under either of the following two restrictions: 1. The block i...
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Intense combinatorial study of balanced incomplete block designs since the time of Fisher and Yates has led to a great many designs with the same numbers of treatments, blocks, and block size. While the basic analysis does not differentiate among different BIBDs with the same parameters, they do differ in their capacity to withstand loss of experimental material. Competing BIBDs are compared he...
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