/* exp(x) function:  sum(x^j/j!, j, 0, 22),numer;  */
x : 2.$  /*  real, independent variable  */
prod : x$  /*  x^1  */
fact : 1.$  /*  1!  */
acc : fact$  /*  x^0/0!, 1st result of sequence  */
for j : 2 thru 23 do ( 
  acc : acc + prod/fact,  /*  J-th result of sequence  */
  prod : prod * x,  /*  x^j  */
  fact : fact * j )$  /*  j!  */
acc, numer;