Irregular total labellings of Ladder

The total edge irregularity strength tes(G) and total vertex irregularity strength tvs(G) are invariants analogous to irregular strength s(G) of a graph G for total labellings. Bača et al. [Discrete Mathematics, 307: 1378-1388, (2007)] determined the bounds and precise values for some families of graphs concerning these parameters. In this paper, we show the exact values of the total edge irregularity strength tes (L_n)= n total vertex irregularity strength and tvs(L_n) = ⌊n/2 ⌋ + 1 for the Ladder L_n.