Generator.lisp

(defun nfib (a b c n)
  (if (= n 0)
	  a
	  (nfib b c (/ (+ b c) a) (1- n))))

(defmacro while (test &body body)
  `(do ()
	   ((not ,test))
	 ,@body))

(defmacro with-gensyms (syms &body body)
  `(let ,(mapcar #'(lambda (x) `(,x (gensym))) syms)
	 ,@body))

(defmacro collect-list (end-condition next-value var)
  "Generates a list based on the next-value provided."
  (with-gensyms (acc)
	`(let ((,acc nil))
	   (while (not ,end-condition)
		 (push ,var ,acc)
		 (setq ,var ,next-value))
	   (nreverse (cons ,var ,acc)))))

(defun range (x y &optional (step 1))
  "Generates a range with an optional step parameter. It is non-inclusive."
  (if (> (abs (- y (+ step x))) (abs (- y x)))
	  nil
	  (nbutlast (collect-list (= x y) (+ x step) x))))

(with-open-file	(f "data.txt" :direction :output :if-exists :supersede)
  (format f
		  "~{~a~%~}"
		  (loop for x in (range 1 2001) collect (nfib 2.0 1 2 x))))

Plotter.py

import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid.axislines import SubplotZero
file = open("data.txt","rU")
xs = []
for line in file:
    xs.append(float(line.strip()))
fig = plt.figure(1)
ax = SubplotZero(fig,111,
    xlabel="N",
    ylabel="Number of Prime Lengthed Chains Less Than or Equal To N Divided By N")
fig.add_subplot(ax)
x = range(1,len(xs)+1)
ax.plot(x,xs)
plt.show()