Some nordhaus- gaddum-type results
نویسندگان
چکیده
A Nordhaus-Gaddum-type result is a (tight) lower or upper bound on the sum or product of a parameter of a graph and its complement. In this paper some variations are considered. First, the sums and products of ψ(G1) and ψ(G2) are examined where G1 ⊕ G2 = K(s, s), and ψ is the independence, domination, or independent domination number, inter alia. In particular, it is shown that the maximum value of the product of the domination numbers of G1 and G2 is b(s/2 + 2) c for s ≥ 3. Thereafter it is shown that for H1⊕H2⊕H3 = Kp, the maximum product of the domination numbers of H1, H2 and H3 is p /27 + Θ(p).
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ورودعنوان ژورنال:
- Journal of Graph Theory
دوره 16 شماره
صفحات -
تاریخ انتشار 1992