2024/12/04 by Reich, Florian
#05C20 #05C63 #Combinatorics (math.CO) #FOS: Mathematics
paper · doi:10.48550/arxiv.2412.03482
Halin showed that every thick end of every graph contains an infinite grid. We extend Halin's theorem to digraphs. More precisely, we show that for every infinite family R of disjoint equivalent out-rays there is a grid whose vertical rays are contained in R. Furthermore, we obtain similar results for in-rays and necklaces.