On local antimagic chromatic number of lexicographic product graphs

نویسندگان

چکیده

Consider a simple connected graph $$G = (V,E)$$ of order p and size q. For bijection $$f : E \to \{1,2,\ldots,q\}$$ , let $$f^+(u) \sum_{e\in E(u)} f(e)$$ where $$E(u)$$ is the set edges incident to u. We say f local antimagic labeling G if for any two adjacent vertices u v, we have \ne f^+(v)$$ . The minimum number distinct values $$f^+$$ taken over all denoted by $$\chi_{la}(G)$$ Let $$G[H]$$ be lexicographic product graphs H. In this paper, obtain sharp upper bound $$\chi_{la}(G[O_n])$$ $$O_n$$ null $$n\ge 3$$ Sufficient conditions even regular bipartite tripartite $$\chi_{la}(G)=3$$ are also obtained. Consequently, successfully determined chromatic infinitely many (connected disconnected) that partially support existence an r-regular such (i) $$\chi_{la}(G)=\chi(G)=k$$ (ii) $$\chi_{la}(G)=\chi(G)+1=k$$ each possible $$r,p,k$$

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

On the chromatic number of the lexicographic product and the Cartesian sum of graphs

Let G[H] be the lexicographic product of graphs G and H and let G⊕H be their Cartesian sum. It is proved that if G is a nonbipartite graph, then for any graph H, χ(G[H]) ≥ 2χ(H)+d k e, where 2k+1 is the length of a shortest odd cycle of G. Chromatic numbers of the Cartesian sum of graphs are also considered. It is shown in particular that for χ–critical and not complete graphs G and H, χ(G ⊕ H)...

متن کامل

On the fractional chromatic number and the lexicographic product of graphs

For graphs G and H let GH] be their lexicographic product and let f (G) = inff(GK n ])=n j n = 1; 2; : : :g be the fractional chromatic number of G. For n 1 set G n = fG j (GK n ]) = nn(G)g. Then lim n!1 G n = fG j f (G) = (G)g: Moreover, we prove that for any n 2 the class G n forms a proper subclass of G n?1. As a by-product we show that if G is a-extremal, vertex transitive graph on (G)(G) ?...

متن کامل

Improved Bounds for the Chromatic Number of the Lexicographic Product of Graphs

An upper bound for the chromatic number of the lexicographic product of graphs which unifies and generalizes several known results is proved. It is applied in particular to characterize graphs that have a complete core. An improved lower bound is also given.

متن کامل

Game Chromatic Number of Cartesian Product Graphs

The game chromatic number χg is considered for the Cartesian product G 2 H of two graphs G and H. We determine exact values of χg(G2H) when G and H belong to certain classes of graphs, and show that, in general, the game chromatic number χg(G2H) is not bounded from above by a function of game chromatic numbers of graphs G and H. An analogous result is proved for the game coloring number colg(G2...

متن کامل

The locating-chromatic number for Halin graphs

Let G be a connected graph. Let f be a proper k -coloring of G and Π = (R_1, R_2, . . . , R_k) bean ordered partition of V (G) into color classes. For any vertex v of G, define the color code c_Π(v) of v with respect to Π to be a k -tuple (d(v, R_1), d(v, R_2), . . . , d(v, R_k)), where d(v, R_i) is the min{d(v, x)|x ∈ R_i}. If distinct vertices have distinct color codes, then we call f a locat...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Acta Mathematica Hungarica

سال: 2023

ISSN: ['0001-5954', '0236-5294', '1588-2632']

DOI: https://doi.org/10.1007/s10474-023-01305-x