zagreb indices belong to better known and better researched topological indices. weinvestigate here their ability to discriminate among benzenoid graphs and arrive at some quiteunexpected conclusions. along the way we establish tight (and sometimes sharp) lower andupper bounds on various classes of benzenoids.

1Čakovec General Hospital, Čakovec, Croatia; 2University Hospital Centre Zagreb, Department of Nephrology, Arterial Hypertension, Dialysis and Transplantation, Zagreb, Croatia; 3Sestre milosrdnice University Hospital Centre, Department of Nuclear Medicine, Zagreb, Croatia; 4University Hospital Centre Zagreb, Department of Dermatology and Venereology, Zagreb, Croatia; 5University of Zagreb Schoo...

Let G be a graph with vetex set V (G) and edge set E(G). The first generalized multiplicative Zagreb index of G is ∏ 1,c(G) = ∏ v∈V (G) d(v) , for a real number c > 0, and the second multiplicative Zagreb index is ∏ 2(G) = ∏ uv∈E(G) d(u)d(v), where d(u), d(v) are the degrees of the vertices of u, v. The multiplicative Zagreb indices have been the focus of considerable research in computational ...

Let D=(V,A) be a digraphs without isolated vertices. The first Zagreb index of digraph D is defined as summation over all arcs, M1(D)=12∑uv∈A(du++dv−), where du+(resp. du−) denotes the out-degree (resp. in-degree) vertex u. In this paper, we give maximal values and set orientations unicyclic graphs with n vertices matching number m (2≤m≤⌊n2⌋).

For a simple graph G with n vertices and m edges, the first Zagreb index and the second Zagreb index are defined as M1(G) = ∑ v∈V d(v) 2 and M2(G) = ∑ uv∈E d(u)d(v). In [34], it was shown that if a connected graph G has maximal degree 4, then G satisfies M1(G)/n = M2(G)/m (also known as the Zagreb indices equality) if and only if G is regular or biregular of class 1 (a biregular graph whose no ...

+ Groenemeyer Institute for Microtherapy, 44799 Bochum, Germany, Department of General Surgery and Traumatology, General Hospital Varazdin, I Mestrovica bb, 42000, Varazdin, Croatia, Croatian Institute of Transfusion Medicine, Petrova ulica, 10000, Zagreb, Croatia, Department of Orthopaedic Surgery, School of Medicine, University of Zagreb, Salata 3b, 10000, Zagreb, Croatia, The Scientific Unit...

the chromatic number of a graph g, denoted by χ(g), is the minimum number of colors such that g can be colored with these colors in such a way that no two adjacent vertices have the same color. a clique in a graph is a set of mutually adjacent vertices. the maximum size of a clique in a graph g is called the clique number of g. the turán graph tn(k) is a complete k-partite graph whose partition...

Merkur Clinical Hospital, Zagreb University School of Medicine, Department of Internal medicine, Zagreb, 1Zadar General Hospital, Department of Nephrology and Dialysis, Zadar, 2Bjelovar General Hospital, Department of Internal medicine, Bjelovar, 3Dubrava University Hospital, Department of Nephrology, Zagreb, 4Dubrovnik General Hospital, Department of Internal medicine, Dubrovnik and 5Rijeka Un...

Let G be a graph. The first Zagreb polynomial M1(G, x) and the third Zagreb polynomial M3(G, x) of the graph G are defined as:     ( ) ( , ) [ ] e uv E G G x x d(u) + d(v) M1 , ( , )  euvE(G) G x x|d(u) - d(v)| M3 . In this paper, we compute the first and third Zagreb polynomials of Cartesian product of two graphs and a type of dendrimers.

A new extension of the generalized topological indices (GTI) approach is carried out to represent “simple” and “composite” topological indices (TIs) in an unified way. This approach defines a GTI-space from which both simple and composite TIs represent particular subspaces. Accordingly, simple TIs such as Wiener, Balaban, Zagreb, Harary and Randić connectivity indices are expressed by means of ...