Forbidden families of configurations
نویسندگان
چکیده
A simple matrix is a (0, 1)-matrix with no repeated columns. For a (0, 1)matrix F , we say that a (0, 1)-matrix A has F as a configuration if there is a submatrix of A which is a row and column permutation of F (trace is the set system version of a configuration). Let ‖A‖ denote the number of columns of A. Let F be a family of matrices. We define the extremal function forb(m,F) = max{‖A‖ : A is m-rowed simple matrix and has no configuration F ∈ F}. We consider some families F = {F1, F2, . . . , Ft} such that individually each forb(m,Fi) has greater asymptotic growth than forb(m,F).
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 59 شماره
صفحات -
تاریخ انتشار 2014