text: In fact,  has a limit at all accumulation points of , except for , ,  and . Accordingly, this allows one to define the powers  by continuity whenever , , except for , ,  and , which remain indeterminate forms.
  Under this definition by continuity, we obtain:
  and , when .
  and , when .
  and , when .
  and , when .
  These powers are obtained by taking limits of  for positive values of . This method does not permit a definition of  when , since pairs  with  are not accumulation points of .
  On the other hand, when  is an integer, the power  is already meaningful for all values of , including negative ones. This may make the definition  obtained above for negative  problematic when  is odd, since in this case  as  tends to  through positive values, but not negative ones.
  Efficient computation with integer exponents
  Computing  using iterated multiplication requires  multiplication operations, but it can be computed more efficiently than that, as illustrated by the following example. To compute , apply Horner's rule to the exponent 100 written in binary:
  .
  Then compute the following terms in order, reading Horner's rule from right to left.
  This series of steps only requires 8 multiplications instead of 99.