From d62ba829dc3a54edc46b7deb581dd244713393f5 Mon Sep 17 00:00:00 2001 From: mjfernez Date: Sun, 2 Dec 2018 19:12:42 -0500 Subject: add code --- 10001prime.py | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 10001prime.py (limited to '10001prime.py') diff --git a/10001prime.py b/10001prime.py new file mode 100644 index 0000000..ecf8139 --- /dev/null +++ b/10001prime.py @@ -0,0 +1,31 @@ +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] -- cgit v1.2.3