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+import PIL, math
+import numpy as np
+
+#Problem 7 - 10,001st prime
+
+#returns a list of every prime up to a certain number
+def listprimes(number):
+	primes = []
+	if (number <=1):
+		return [1]
+	a = np.ones(number)
+	a[0]=0
+	a[1]=0#1 and 0 are not prime
+	##Sieve of eratosthenes
+	for i in range(2,int(math.ceil(math.sqrt(number)))):
+		if(a[i]==1):
+			j = i**2 #cross out all the multiples of i, starting with its square
+			while(j < number):
+				a[j] = 0
+				j+=i
+	
+	for k in range(2, number):
+		#is prime
+		if(a[k]==1):
+			primes.append(k)
+	return primes
+
+out_list = listprimes(1000000)
+print out_list
+#return 10,001th prime factor
+print out_list[10000]