Iteration loop
 

Not even sure I'm in the right place for this question, and from the looks of this forum, most of you are out of my league, so hopefully this will be an easy question for you. I have a variable, "k", that is directly dependant upon another variable "P". The way I have been calculating "k" is by assuming a "P" to start with. Once I have "k", a series of other variables are calculated, ultimately arriving at a calculated "P". I then go and input the calculated "P" to arrive at another "k" and calculated "P" and so on and so forth, iterating manually. I want to set up the equations so the "k" assumes a "P", then uses the calculated "P" in a loop that eventually converges. I'm looking to get the actual "P" and "k" out of the iteration. Any help would be greatly appreciated.