On the lower bound of k-maximal digraphs
نویسندگان
چکیده
For a digraph D, let λ(D) be the arc-strong-connectivity of D. For an integer k > 0, a simple digraph Dwith |V (D)| ≥ k + 1 is k-maximal if every subdigraph H of D satisfies λ(H) ≤ k but for adding new arc to D results in a subdigraph H ′ with λ(H ) ≥ k + 1. We prove that if D is a simple k-maximal digraph on n > k + 1 ≥ 2 vertices, then |A(D)| ≥ n 2 + (n − 1)k + n k + 2 1 + 2k − k + 2 2
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 339 شماره
صفحات -
تاریخ انتشار 2016