If sticker collectors pool their acquisitions but collectors leave the pool as soon as they're finished, how much does each collector spend?

output.txt

Album has 638 stickers
50 trials for each pool size
Collectors      Waste           Waste per collector     Mean Min bought Mean Max bought
1               3921.400000     3921.400000             4559.400000     4559.400000
2               4464.800000     2232.400000             2463.120000     3277.680000
3               5422.080000     1807.360000             2009.160000     2993.760000
4               5517.640000     1379.410000             1592.040000     2582.040000
5               6359.600000     1271.920000             1459.800000     2700.000000
6               6726.600000     1121.100000             1318.200000     2594.760000
7               7176.520000     1025.217143             1213.560000     2506.800000
8               7732.520000     966.565000              1178.280000     2606.640000
9               7711.920000     856.880000              1081.800000     2442.120000
10              8506.360000     850.636000              1069.080000     2612.160000
11              8837.120000     803.374545              1028.160000     2554.440000
12              9001.800000     750.150000              1002.600000     2488.200000
13              9497.320000     730.563077              979.080000      2531.280000
14              9190.520000     656.465714              937.800000      2448.360000
15              9705.960000     647.064000              924.480000      2365.920000
16              10108.120000    631.757500              901.080000      2490.360000
17              9856.760000     579.809412              881.280000      2285.400000
18              10193.040000    566.280000              867.000000      2306.520000
19              10359.400000    545.231579              849.240000      2324.400000
20              10716.080000    535.804000              841.920000      2380.800000
Waste is the number of excess stickers

stickers.py

import random

class Collection:
	def __init__(self,num_stickers):
		self.num_stickers = num_stickers
	
	def pack(self):
		return [random.randrange(self.num_stickers) for i in range(6)]

class Album:
	bought = 0

	def __init__(self,collection):
		self.collection = collection
		self.got = [False]*self.collection.num_stickers

	def finished(self):
		return False not in self.got

def collect(collection,num_albums):
	albums = [Album(collection) for i in range(num_albums)]
	doubles = []
	unfinished = albums[:]
	done = False
	while sum(album.finished() for album in albums)<num_albums:
		buyer = random.choice(unfinished)
		buyer.bought += 6
		pack = collection.pack()
		for sticker in pack:
			double = True
			order = albums[:]
			random.shuffle(order)
			for album in order:
				if not album.got[sticker]:
					album.got[sticker] = True
					double = False
					if album.finished():
						unfinished.remove(album)
					break
			if double:
				doubles.append(sticker)

	bought = [album.bought for album in albums]
	return (len(doubles),min(bought),max(bought))

if __name__ == '__main__':
	num_stickers = 638
	num_trials = 50
	collection = Collection(num_stickers)

	print("Album has %i stickers" % num_stickers)
	print("%i trials for each pool size" % num_trials)
	print('Collectors\tWaste\t\tWaste per collector\tMean Min bought\tMean Max bought')
	for i in range(1,21):
		t_doubles = 0
		t_min_bought = 0
		t_max_bought = 0
		for j in range(num_trials):
			doubles, min_bought, max_bought = collect(collection,i)
			t_doubles += doubles
			t_min_bought += min_bought
			t_max_bought += max_bought
		t_doubles /= num_trials
		t_min_bought /= num_trials
		t_max_bought /= num_trials
		print('%i\t\t%f\t%f\t\t%f\t%f' % (i,t_doubles,t_doubles/i,t_min_bought,t_max_bought))

	print("Waste is the number of excess stickers")