
theorem
for L being non empty ZeroStr
for a,b,c being Element of L
holds <%c,b,a%>.0 = c & <%c,b,a%>.1 = b & <%c,b,a%>.2 = a &
      for n being Nat st n >= 3 holds <%c,b,a%>.n = 0.L by qua1;
