how do I update cels through iteration

Hi

I'll appreciate if someone can provide with assistance to do the following.
I have an array of cells with formulas with each cell a function of the
previous one. Now, I want a macro that iterates across the array so that
during each iteration the array is updated using parameters outside the array
and the last values computed in the array. Of course I'll have an if
condition in the array such that if the value of another cell called
iteration is zero then initial conditions are defined, otherwise update the
cells based on previous values. Also, the iteration cell needs to be updated
setting its value equals to the counter in the loop of the macro that runs
the iteration.

Many thanks