Python: An iterating function
<p>I am trying to write a program that iterates for me in the form of x<sub>n+1</sub> = x<sub>n</sub><sup>2</sup> + c. How do I do this?</p>

<p>For example, for c = 1 and x<sub>0</sub> = 1/2</p>

<p>(1/2)<sup>2</sup> + 1 = 5/4,<br>
(5/4)<sup>2</sup> + 1 = 25/16 + 1 = 41/16<br>
... etc</p>

<p>My code doesn't work here:</p>

<pre><code>def main():
   import math
   print("This program iterates a function of the form x^2 + c:")
   x=complex(input("Enter a seed value:"))
   c=complex(input("Enter a value for c"))

for i in range(50):
   f(0) = x*x + c
   f(i) = f(i-1)*f(i-1) + c
   print(f(i))
main()
</code></pre>

<p>Python doesn't allow me to use <code>f(0)</code> or <code>f(i)</code> like matlab, what's the alternative to this?</p>
