Sign-Compatibility of Some Derived Signed Graphs

A signed graph (or sigraph in short) is an ordered pair S = (Su, σ), where Su is a graph G = (V, E), called the underlying graph of S and σ : E → {+1, −1} is a function from the edge set E of Su into the set {+1, −1}, called the signature of S. A sigraph S is sign-compatible if there exists a marking µ of its vertices such that the end vertices of every negative edge receive ‘−1’ marks in µ and no positive edge does so. In this paper, we characterize S such that its ×-line sigraphs, semi-total line sigraphs, semi-total point sigraphs and total sigraphs are sign-compatible

On •-Line Signed Graphs L_•(S)

A signed graph (or sigraph for short) is an ordered pair S = (Su,σ), where Su is a graph, G = (V,E), called the underlying graph of S and σ : E → {+,−} is a function from the edge set E of Su into the set {+,−}. For a sigraph S its •-line sigraph, L•(S) is the sigraph in which the edges of S are represented as vertices, two of these vertices are defined adjacent whenever the corresponding edges in S have a vertex in common, any such L-edge ee′ has the sign given by the product of the signs of the edges incident with the vertex in e ∩ e′. In this paper we establish a structural characterization of •-line sigraphs, extending a well known characterization of line graphs due to Harary. Further we study several standard properties of •-line sigraphs, such as the balanced •-line sigraphs, sign-compatible •-line sigraphs and C-sign-compatible •-line sigraphs

Negation switching invariant signed graphs

A signed graph (or, $sigraph$ in short) is a graph G in which each edge x carries a value $\sigma(x) \in \{-, +\}$ called its sign. Given a sigraph S, the negation $\eta(S)$ of the sigraph S is a sigraph obtained from S by reversing the sign of every edge of S. Two sigraphs $S_{1}$ and $S_{2}$ on the same underlying graph are switching equivalent if it is possible to assign signs `+' (`plus') or `-' (`minus') to vertices of $S_{1}$ such that by reversing the sign of each of its edges that has received opposite signs at its ends, one obtains $S_{2}$. In this paper, we characterize sigraphs which are negation switching invariant and also see for what sigraphs, S and $\eta (S)$ are signed isomorphic

On •-Line Signed Graphs L•(S)

A signed graph (or sigraph for short) is an ordered pair S = (Su,σ), where Su is a graph, G = (V,E), called the underlying graph of S and σ : E → {+,−} is a function from the edge set E of Su into the set {+,−}. For a sigraph S its •-line sigraph, L•(S) is the sigraph in which the edges of S are represented as vertices, two of these vertices are defined adjacent whenever the corresponding edges in S have a vertex in common, any such L-edge ee′ has the sign given by the product of the signs of the edges incident with the vertex in e ∩ e′. In this paper we establish a structural characterization of •-line sigraphs, extending a well known characterization of line graphs due to Harary. Further we study several standard properties of •-line sigraphs, such as the balanced •-line sigraphs, sign-compatible •-line sigraphs and C-sign-compatible •-line sigraphs

On Some Properties of Addition Signed Cayley Graph <inline-formula><math display="inline"><semantics><msubsup><mo mathvariant="bold-sans-serif">Σ</mo><mi mathvariant="bold-italic">n</mi><mo mathvariant="bold">∧</mo></msubsup></semantics></math></inline-formula>

We define an addition signed Cayley graph on a unitary addition Cayley graph Gn represented by Σn∧, and study several properties such as balancing, clusterability and sign compatibility of the addition signed Cayley graph Σn∧. We also study the characterization of canonical consistency of Σn∧, for some n

On Some Properties of Addition Signed Cayley Graph &Sigma;n&and;

We define an addition signed Cayley graph on a unitary addition Cayley graph Gn represented by &Sigma;n&and;, and study several properties such as balancing, clusterability and sign compatibility of the addition signed Cayley graph &Sigma;n&and;. We also study the characterization of canonical consistency of &Sigma;n&and;, for some n

On Some Properties of Signed Cayley Graph <i>S_n</i>

We define the signed Cayley graph on Cayley graph Xn denoted by Sn, and study several properties such as balancing, clusterability and sign-compatibility of the signed Cayley graph Sn. Apart from it we also study the characterization of the canonical consistency of Sn, for some n