def is_prime(i, list_primes): # test if i is a prime
if i in list_primes: # check to see if i is already a known prime
return True # i is a known prime
for prime in list_primes: # check each known prime
if i % prime == 0: # if the known prime evenly divides i, then:
return False # i CANNOT be prime
return True # if we reach this point, i MUST be prime
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n = 25 #######the nth prime we are looking for, make your changes here########
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list_primes= [2] # this is our list of known prime numbers, we start it off with 2
i = 2 # a counter to start at 2
while len(list_primes) < n: # while we haven't found the nth prime
i = i + 1 # the next number to check if it is prime
if is_prime(i, list_primes): # check if is prime
list_primes.append(i) # if it is prime, add it to the list of known primes
output_message = "The %dth prime is: %d" % (n, list_primes[n-1]) # simple output form
print(output_message) # print our output