On prime labellings
نویسندگان
چکیده
منابع مشابه
On prime labellings
Let G =( V, E) be a graph. A bijectionf: V+{ 1,2,. ., 1 VI} IS called a prime labelling if for each e = {u, u} in E, we have GCD(f(u),f(u))= 1. A graph admits a prime labelling is called a prime graph. Around ten years ago, Roger Entringer conjectured that every tree is prime. So far, this conjecture is still unsolved. In this paper, we show that the conjecture is true for trees of order up to ...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1994
ISSN: 0012-365X
DOI: 10.1016/0012-365x(92)00477-9