A logical system of comparative exegesis, Ze led by constant reference to Sanskrit, its nearest ally, and to the her Iranian dialects, is the best means of recovering the lost of rise of the Zend texts.
If we wish merely to enumerate those whose partitions contain the figure 0, and do not therefore contain any power of a as a factor, we have the generator ze 1-z2.1-z3.1-z4....1-z0.