A set $S$ of vertices is a $[1,2]$-set of a graph $G$ if every vertex $v$ not in $S$ is adjacent to at least one but no more than two vertices in $S$. The minimum cardinality of a $[1,2]$-set is the $[1,2]$-domination number. In this paper, we present two upper bounds on the $[1,2]$-domination number of trees in terms of the order, number of support vertices and number of leaves. Furthermore, extremal trees reaching one of these two bounds are provided.
[1] J. Cáceres, C. Hernando, M. Mora, I.M. Pelayo, and M.L. Puertas González, Perfect and quasiperfect domination in trees, Appl. Analysis Discrete Math. 10 (2016), 46–64. https://doi.org/10.2298/AADM160406007C
Amjadi, J. , Ebadi, M. , Sheikholeslami, S. M. and Volkmann, L. (2026). Upper bounds for $[1,2]$-domination number in trees. Communications in Combinatorics and Optimization, (), -. doi: 10.22049/cco.2026.31357.2831
MLA
Amjadi, J. , , Ebadi, M. , , Sheikholeslami, S. M. , and Volkmann, L. . "Upper bounds for $[1,2]$-domination number in trees", Communications in Combinatorics and Optimization, , , 2026, -. doi: 10.22049/cco.2026.31357.2831
HARVARD
Amjadi, J., Ebadi, M., Sheikholeslami, S. M., Volkmann, L. (2026). 'Upper bounds for $[1,2]$-domination number in trees', Communications in Combinatorics and Optimization, (), pp. -. doi: 10.22049/cco.2026.31357.2831
CHICAGO
J. Amjadi , M. Ebadi , S. M. Sheikholeslami and L. Volkmann, "Upper bounds for $[1,2]$-domination number in trees," Communications in Combinatorics and Optimization, (2026): -, doi: 10.22049/cco.2026.31357.2831
VANCOUVER
Amjadi, J., Ebadi, M., Sheikholeslami, S. M., Volkmann, L. Upper bounds for $[1,2]$-domination number in trees. Communications in Combinatorics and Optimization, 2026; (): -. doi: 10.22049/cco.2026.31357.2831