The concept of the shortest vectorial addition chains is considered to
be an optimal approach for computing a monomial Pi(i=1)(p)x(i)(ni) wi
th the minimum number of multiplications. In this paper, some properti
es of the shortest vectorial addition chain are presented. Furthermore
, an approach to achieve the shortest chains in some special cases is
proposed. The correctness of these properties and the optimality of th
is approach are also shown.