All trees contain a large induced subgraph having all degrees 1 (mod k)
نویسندگان
چکیده
We prove that, for integers n ≥ 2 and k ≥ 2, every tree with n vertices contains an induced subgraph of order at least 2b(n + 2k− 3)/(2k− 1)c with all degrees congruent to 1 modulo k. This extends a result of Radcliffe and Scott, and answers a question of Caro, Krasikov and Roditty. † Supported in part by NSF 9401351
منابع مشابه
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 175 شماره
صفحات -
تاریخ انتشار 1997