Hi John. The degrees in distance is as follows and are generated by a quake of M>7.0 and larger. The phenomenon has been seen with quakes a little smaller, but for the most part M>7.0 is the minimum. The degrees are from the epicenter of the quake.

0-5 Classical and locally triggered aftershocks. Earthquakes in this region are commonly followed by numerous aftershocks within 5 degrees.
9-10
17-19
34-36
43-45
59-61
71-73*
142-146*
176-180

*The strongest triggering is always expected to be along the shadow zone boundary between 102-107 degrees and 142-146 degrees from the epicenter and near the antipode if that region is at all seismic. Usually 10 to 12 days is the maximum time this can be seen. Take Care…Don in creepy town