func resetTable(table []divisor) {
	if table != nil && table[0].bbb != nil {
		for i := 0; i < len(table); i++ {
			table[i].bbb = nil
			table[i].nbits = 0
			table[i].ndigits = 0
		}
	}
}

func TestStringPowers(t *testing.T) {
	var p Word
	for b := 2; b <= 16; b++ {
		for p = 0; p <= 512; p++ {
			if testing.Short() && p > 10 {
				break
			}
			x := nat(nil).expWW(Word(b), p)
			xs := x.utoa(b)