Discussiones Mathematicae Graph Theory 16(1) (1996) 17-26
DOI: https://doi.org/10.7151/dmgt.1020
RADII AND CENTERS IN ITERATED LINE DIGRAPHS
Martin Knor Slovak Technical University, Faculty of Civil
Engineering |
L'udovít Niepel Comenius University, Faculty of Mathematics and
Physics |
Abstract
We show that the out-radius and the radius grow linearly, or ``almost" linearly, in iterated line digraphs. Further, iterated line digraphs with a prescribed out-center, or a center, are constructed. It is shown that not every line digraph is admissible as an out-center of line digraph.
Keywords: center, digraph, line digraph, radius.
1991 Mathematics Subject Classification: 05C20, 05C12.
References
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[5] | M. Knor, L'. Niepel and L'. Soltés, Centers in Iterated Line Graphs, Acta Math. Univ. Comenianae LXI, 2 (1992) 237-241. |
[6] | M. Knor, L'. Niepel and L'. Soltés, Distances in Iterated Line Graphs, Ars Combin. (to appear). |
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