Cancellative pairs of families of sets
نویسندگان
چکیده
A pair (~, ~) of families of subsets of an n-element set X is cancellative if, for all A, A' e .~ and B, B' E ~, the following conditions hold: A\B = A ' \ B ~ A =A' and BkA =B'kA~B = B'. We prove that every such pair satisfies I.~11~1 < 0 ~, where 0 ~2.3264. This is related to a conjecture of ErdSs and Katona on cancellative families and to a conjecture of Simonyi on recovering pairs. For the latter, our result gives the best known upper bound.
منابع مشابه
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عنوان ژورنال:
- Eur. J. Comb.
دوره 16 شماره
صفحات -
تاریخ انتشار 1995