[Jprogramming] arithmetic sequence

[alessandro codenotti]

The answer expected is exactly the one provided by Henry's code which, for the first 10 terms, just copy/pasting from the J console, is:

   next=.5&(0 3 + *)
   (i. 10) next 1 0
      1       0
      5       3
     25      18
    125      93
    625     468
   3125    2343
  15625   11718
  78125   58593
 390625  292968
1953125 1464843

What I'm now speaking about is only how to improve this code, since it seems wasting a huge amount of time too me, though I'm not sure about it, being a beginner in J!

Alessandro