#!/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

	# Please note that the ``is`` operator checks wether the
	# two references are the same object, basically by comparing
	# their pointers.
	#
	# The ``==`` operator accesses the ``__eq__`` method of the 
	# object that *compares* the other object to itself.
	#
	# Because ``a/b`` **cannot** return the same object as ``math.pi``,
	# the latter was created when the module ``math`` was initialized,
	# this will **always** evaluate to False.