pi/2-ANGLE YAO GRAPHS ARE SPANNERS
We show that the Yao graph Y-4 in the L-2 metric is a spanner with stretch factor 8 root 2(26+ 23 root 2). Enroute to this, we also show that the Yao graph Y-4(infinity) in the L-infinity metric is a plane spanner with stretch factor 8.
yao graph spanner y4