slightly simpler math.Pow per gri's suggestion
slightly simpler math.Pow per gri's suggestion

R=gri
DELTA=28  (2 added, 9 deleted, 17 changed)
OCL=19707
CL=19707
abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go,abustany/go