On 3-pushdown graphs with large separators
نویسندگان
چکیده
For an integer s let ZS(n), the s-iterated logarithm function, be defined inductively: [O(n) = n, [8+1(n) = log2(l8(n)) for s 2:: o. We show that for every fixed s and all n large enough, there is an n-vertex 3-pushdown graph whose smallest separator contains at least n(n/[8(n)) vertices.
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عنوان ژورنال:
- Combinatorica
دوره 9 شماره
صفحات -
تاریخ انتشار 1989