Eight Octads Suffice
نویسنده
چکیده
The following question is answered: What is the minimum number of octads required to define a Steiner system Y(5, 8, 24)? A set of octads is said to define a particular Steiner system if it is a subset of the special octads of that system, but of no other. As the title suggests, it is possible to produce a set of eight octads which defines the system, whereas any collection of seven octads is a subset of no Steiner system or of more than one. Note that, given an element of S,,, one is now able to decide whether it is in M,, by simply applying it to a defining set of eight octads. If the images are in the system the element must be in M,,.
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عنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 36 شماره
صفحات -
تاریخ انتشار 1984