Added Exercise 3

ex_01_03.py

@@ -0,0 +1,14 @@
+#!/usr/bin/python3
+
+import math
+
+def bailey_borwein_plouffe_pi(n):
+	result = 0
+	for k in range(n):
+		result += (1/16)**k * ( 4/(8*k + 1) - 2/(8*k + 4) - 1/(8*k + 5) - 1/(8*k + 6))
+
+	return result
+
+if( __name__ == "__main__"):
+
+	assert bailey_borwein_plouffe_pi(1000) == math.pi