Hi everybody,

I wanted have a formula in every third row and in the last row
irrespective of whether its is the row that what I need. I think this
question is not so clear, so I'm giving one example here.

B1=26(can have any +ve integer value)
So now A1=If(B1=1,randbetween(10,20))
then I need A4=(B1=4,randbetween(10,20))
then I need A7=(B1=7,randbetween(10,20))