Linked Balanced Designs are Symmetric BIBD’s
نویسندگان
چکیده
Abstract Let A be a reduced incidence relation between n lines and m points. Suppose that (a) Through each two points there pass λ lines (b) Each two lines intersect in μ points. If λ μ = = 1 assume, moreover, that there are four points no three of which are on one line. Then n m = , λ μ = , and there is a number r such that all lines have r points and through each point there pass r lines. The number r is given by r r n ( ) ( ) − = − 1 1 λ .
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