replicate run
I have this design with 4 discrete factors with 3 levels and I got 9 runs without replicates. I am trying to add replicate to the design and when I added 1 replicate run, the number of runs doubled (from 9 to 18). I thought if I mention 1 then it will add 1 replicate run. I am wrong or this is adding 9 runs because I have dicrete factors?