Exemple #1
0
def q10():
    pg = gen_primes()
    sum = 0
    prime = next(pg)
    while prime < 2000000:
        sum += prime
        prime = next(pg)

    print("Primes < 2M, summed:", sum)
def summation_of_primes(limit):
    """
    adds all the primes up to some limit

    limit (int): limit, exclusive
    returns (int): result
    """
    stub = Stub()
    stub.start()
    
    result = 0
    for prime in gen_primes(limit):
        result += prime

    return result
Exemple #3
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def q3():
    """
	Uses the trial division method in order to find
	the prime factors.
	"""
    num = 600851475143
    pg = gen_primes()
    prime = next(pg)

    # keep track of all the factors
    factors = []

    # no need to go larger than sqrt(num)
    while (prime < floor(sqrt(num))):
        if (num % prime == 0):
            factors.append(prime)
        prime = next(pg)

    return factors
Exemple #4
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import math
import itertools
from euler import is_prime, gen_primes

ELEMENTS_NUM = 4
SEQUENCE_SIZE = 3
START_NUMBER = 10 ** (ELEMENTS_NUM-1)
MAX_NUMBER = (10**ELEMENTS_NUM)
MAX_INTERVAL = int(MAX_NUMBER/SEQUENCE_SIZE)

possible_primes = (prime for prime in gen_primes(limit=MAX_NUMBER) if prime >= START_NUMBER)

primes_seq = []
for sequence_first in possible_primes:
	for interval in xrange(2, MAX_INTERVAL, 2):
		sequence_second = sequence_first+interval
		if sequence_second > MAX_NUMBER or not is_prime(sequence_second):
			continue
		sequence_third = sequence_second+interval
		if sequence_third > MAX_NUMBER or not is_prime(sequence_third):
			continue
		list_1 = [d for d in str(sequence_first)]
		list_2 = [d for d in str(sequence_second)]
		list_3 = [d for d in str(sequence_third)]
		#- Sorting the digits list to compare them later, if the don't have the same order they aren't equal -#
		list_1.sort()
		list_2.sort()
		list_3.sort()
		#- Checking if the 3 primes with equal intervals are permutations of one another and have 4 elements -#
		if  list_1 == list_2 == list_3:
			primes_seq.append((sequence_first, sequence_second, sequence_third))
Exemple #5
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def q7():
	pg = gen_primes()
	for _ in range(10000):
		next(pg)
	print("10,001th prime:", next(pg))
Exemple #6
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import math
import itertools
from euler import gen_primes, is_prime

A_LIMIT = 1000
B_LIMIT = 1000

product = (0, 0)
max_n = 0
for a in xrange(-A_LIMIT+1, A_LIMIT):
	#- b has to be a primer number always -#
	for b in gen_primes(B_LIMIT):
		for n in itertools.count():
			#- Absolute value of the quadratic formula result -#
			num = abs((n**2) + (a*n) + b)
			if not is_prime(num):
				break
		if n > max_n:
			max_n = n
			product = (a, b)
a, b = product
print "n = %d, a = %d, b = %d, a*b = %d" % (max_n, a, b, a*b)
Exemple #7
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import math
import itertools
from euler import gen_primes

print sum(prime for prime in gen_primes(2*10**6))
Exemple #8
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import math
import itertools
from euler import is_prime, gen_primes

def is_circular_prime(prime):
	digits = [c for c in str(prime)]
	for x in xrange(0,len(digits)):
		digits.append(digits.pop(0))
		rotated_num = int(''.join(digits)) 
		if not is_prime(rotated_num):
			return False
	return True

print len([prime for prime in gen_primes(1000000) if is_circular_prime(prime)])
Exemple #9
0
import math
from euler import is_prime, gen_primes

LIMIT = 10**6
primes_list = list(gen_primes(LIMIT))
primes_set = set()

start_offset = 0
end_offset = 0
cons_primes = []
nums_sum = 0
largest_cons_primes = []
while True:
	try:
		current_prime = primes_list[end_offset]
	except IndexError:
		start_offset += 1
		if start_offset > len(primes_list):
			break
		end_offset = start_offset
		cons_primes = []	
		nums_sum = 0
	cons_primes.append(current_prime)
	nums_sum += current_prime
	if nums_sum > LIMIT:
		start_offset += 1
		end_offset = start_offset
		cons_primes = []
		nums_sum = 0
		continue
	if is_prime(nums_sum) and len(cons_primes) > len(largest_cons_primes):