import wget

pre = 'http://arxiv.org/pdf/'
end = '.pdf'
date = 1601
fix = 1000



while True:
	url = pre + str(date).zfill(4) + "." + str(fix).zfill(5) + end
	try:
		wget.download(url)
	except ValueError:
		print "does not exist"
	if fix < 1:
		date -= 1
		fix = 99999
	fix -= 1