Cordial labeling
Open AccessArticleTribonacci Cordial Labeling of Some Snake Graphs
Ariel C. Pedrano* and Melaine Vieve S. Gudin
Annals of Communications in Mathematics 2025,
8 (3),
393-405
DOI: https://doi.org/10.62072/acm.2025.080306
ABSTRACT.An injective function \( f : V(G) \to \{T_0, T_1, T_2, \ldots, T_n\} \), where \( n = |V(G)| - 1 \), is said to be a Tribonacci cordial labeling if the induced function \( f^{*} : E(G) \to \{0,1\} \) defined by \( f^{*}(uv) = (f(u) + f(v)) \pmod 2 \) satisfies the condition \( |e_f(0) - e_f(1)| \le 1 \), where \( e_f(0) \) is the number of edges with label \( 0 \) and \( e_f(1) \) is the number of edges with label \( 1 \). A graph that admits such labeling is called a Tribonacci cordial graph. In this paper, we determine the Tribonacci cordial labeling of Triangular Snake Graph \( TS_n \), Double Triangular Snake Graph \( DT(S_n) \), Quadrilateral Snake Graph \( QS_n \), Double Quadrilateral Snake Graph \( D(QS_n) \), and Cycle Quadrilateral Snake Graph \( C(QS_n) \).
Open AccessArticleOn Edouard Product Cordial Labeling of Some Graphs
Jan Carl M. Vertudes
Annals of Communications in Mathematics 2026,
9(1),
3
DOI: https://doi.org/10.62072/acm.2026.09003
Abstract: Let \( G \) be a graph. An Edouard Product Cordial Labeling (EPCL) of a graph \( G \) with \( |V(G)| = n \) is an injective function \( f : V(G) \rightarrow \{E_0, E_1, E_2, \ldots, E_{n-1}\} \) where \( E_i \) is the \( i \)th Edouard number \( (i = 0,1,2,3,\ldots,n) \) that induces a function \( f^* \) defined by\(f^*(uv) = (f(u)f(v)) \; (\text{mod } 2)\) for all edge \( e = uv \) such that \( |e_f^*(0) - e_f^*(1)| \leq 1 \) where \( e_f^*(0) \) is the number of vertices labeled with 0 and \( e_f^*(1) \) is the number of vertices labeled with 1. The graph that satisfies the condition of an edouard product cordial labeling is called an edouard product cordial graph (EPCG).
Open AccessArticleOn Lucas Product Cordial Labeling of Some Snake Graphs
Cherry T. Magoncia and Eva D. Benacer*
Annals of Communications in Mathematics 2026,
9(1),
7
DOI: https://doi.org/10.62072/acm.2026.09007
Abstract:An injective function \( f : V(G) \rightarrow \{L_1, L_2, \ldots, L_n\} \), where \( L_i \) is the \( i \)th Lucas number, is called a Lucas product cordial labeling if the induced function satisfies \( |e_f^*(0) - e_f^*(1)| \leq 1 \). A graph which admits Lucas product cordial labeling is called Lucas product cordial graph. In this paper, we determined the Lucas Product Cordial Labeling of Quadrilateral Snake Graph Qn, Cycle Quadrilateral Snake Graph CQn, and Alternate Triangular Snake Graph A(Tn).




