Infinite friendship graphs with infinite parameters
نویسندگان
چکیده
منابع مشابه
Infinite friendship graphs with infinite parameters
We study infinite graphs in which every set of κ vertices has exactly λ common neighbours. We prove that there exist 2σ such graphs of each infinite order σ if κ is finite and that for κ infinite there are 2λ of them of order λ and none of cardinality greater than λ (assuming the GCH). Further, we show that all a priori admissible chromatic numbers are in fact possible for such graphs.
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series B
سال: 1991
ISSN: 0095-8956
DOI: 10.1016/0095-8956(91)90087-z