Rana Khoeilar
Department of Mathematics Azarbaijan Shahid Madani University Tabriz-Iran
[ 1 ] - Co-Roman domination in trees
Abstract: Let G=(V,E) be a graph and let f:V(G)→{0,1,2} be a function. A vertex v is protected with respect to f, if f(v)>0 or f(v)=0 and v is adjacent to a vertex of positive weight. The function f is a co-Roman dominating function, abbreviated CRDF if: (i) every vertex in V is protected, and (ii) each u∈V with positive weight has a neighbor v∈V with f(v)=0 such that the func...
[ 2 ] - A note on the first Zagreb index and coindex of graphs
Let $G=(V,E)$, $V={v_1,v_2,ldots,v_n}$, be a simple graph with$n$ vertices, $m$ edges and a sequence of vertex degrees$Delta=d_1ge d_2ge cdots ge d_n=delta$, $d_i=d(v_i)$. Ifvertices $v_i$ and $v_j$ are adjacent in $G$, it is denoted as $isim j$, otherwise, we write $insim j$. The first Zagreb index isvertex-degree-based graph invariant defined as$M_1(G)=sum_{i=1}^nd_i^2$, whereas the first Zag...
[ 3 ] - The annihilator-inclusion Ideal graph of a commutative ring
Let R be a commutative ring with non-zero identity. The annihilator-inclusion ideal graph of R , denoted by ξR, is a graph whose vertex set is the of allnon-zero proper ideals of $R$ and two distinct vertices $I$ and $J$ are adjacentif and only if either Ann(I) ⊆ J or Ann(J) ⊆ I. In this paper, we investigate the basicproperties of the graph ξR. In particular, we showthat ξR is a connected grap...
[ 4 ] - Co-Roman dominating of girds
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نویسندگان همکار