I'm with you there. I didn't mean to imply that programmers don't need to know math. To the contrary, I find it very useful and keep a graphing calculator on my desk. I was just pointing out that knowing the value of PI isn't strictly necessary for this example, because by writing a quick script, one can determine the behavior of the sequence and figure out an appropriate stopping condition. The rest of it is just translating a formula into code.

How many other constants have you memorized? e? phi? sqrt(2)? and you know all those to 5 decimals? When I conduct interviews I try really really hard to set aside the things that I know and give candidates an opportunity to tell (or show) me what they know. Someone not having a constant memorized is not a show stopper, as I am after the logical thought processs.