Let be an atomic partially ordered set (briefly, a poset) with a minimum element , and let be the set of all nontrivial ideals of . The essential graph of , denoted by , is an undirected, simple graph with the vertex set and two distinct vertices are adjacent in if and only if is an essential ideal of . We study the connections between the graph-theoretic properties of this graph and the algebraic properties of a poset. We prove that is connected with diameter at most three. Furthermore, all posets are characterized based on the diameters of their essential graphs. Also, all posets with planar are classified. Among other results, the clique number and chromatic number of are determined.
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Articles in Press, Accepted Manuscript Available Online from 29 June 2025
Nikandish, R. , Eskandari, E. and Motamedinasab, A. (2025). On the essential graph of a poset. Communications in Combinatorics and Optimization, (), -. doi: 10.22049/cco.2025.29478.2093
MLA
Nikandish, R. , , Eskandari, E. , and Motamedinasab, A. . "On the essential graph of a poset", Communications in Combinatorics and Optimization, , , 2025, -. doi: 10.22049/cco.2025.29478.2093
HARVARD
Nikandish, R., Eskandari, E., Motamedinasab, A. (2025). 'On the essential graph of a poset', Communications in Combinatorics and Optimization, (), pp. -. doi: 10.22049/cco.2025.29478.2093
CHICAGO
R. Nikandish , E. Eskandari and A. Motamedinasab, "On the essential graph of a poset," Communications in Combinatorics and Optimization, (2025): -, doi: 10.22049/cco.2025.29478.2093
VANCOUVER
Nikandish, R., Eskandari, E., Motamedinasab, A. On the essential graph of a poset. Communications in Combinatorics and Optimization, 2025; (): -. doi: 10.22049/cco.2025.29478.2093