def solve(start, end, required_results):
primes = primesieve.generate_n_primes(0x10000)
results = []
x = start # 0b10000000000000000000000000000001
while x < end: # 0b100000000000000000000000000000000:
deviders = []
str_x = bin(x)[2:]
for b in range(2, 11):
x_in_base = int(str_x, b)
half_x = x_in_base >> 1
devider = 1
for p in primes:
if p > half_x:
break
if 0 == x_in_base % p:
devider = p
break
if 1 == devider:
break
deviders.append(devider)
else:
results.append(
"%s %s" %
(str_x, ' '.join([str(devider)
for devider in deviders]).strip()))
if len(results) >= required_results:
break
x += 2
return results
def largest_factor(num, number_of_spokes = 3):
spokes = generate_n_primes(n)
wheel = reduce(lambda x, y: x * y, spokes)
composites = []
for i in range(1, wheel):
if all( i % k != 0 for k in spokes):
composites.append(i)
for factor in spokes:
if num % factor == 0 and n > factor:
num //= factor
while num % factor == 0:
num //= factor
if num == 1:
return factor
multiple = 0
limit = num**0.5
while factor < limit:
for step in composites:
factor = multiple + step
if num % factor == 0 and factor > 1:
num //= factor
while num % factor == 0:
num //= factor
if num == 1: return factor
limit = num**0.5
multiple += wheel
return num
def solve(k, modulus=None):
"""Calculate the smallest number with 2**k divisors."""
n = 1
costs = primesieve.generate_n_primes(k) # more than necessary
for i in range(k):
cost = heapq.heappop(costs)
heapq.heappush(costs, cost**2)
n *= cost
if modulus:
n %= modulus
return n
def compute_provisional_chunks(self, start_value, nvalues, nchunks, save_opts):
logger.info("computing provisional chunks, starting from {}".format(start_value))
next_prime = primesieve.generate_n_primes(1, start_value)
logger.info("next_prime for start_value={} is {}".format(start_value, next_prime))
m6_start = next_prime[0] % 6
logger.info("m6_start is {}".format(m6_start))
if m6_start == 1:
logger.info("m6_start is {}, so using start_pos = 0".format(m6_start))
prime_start_pos = 0
else:
logger.info("m6_start is {}, so using start_pos = 5".format(m6_start))
prime_start_pos = 5
linkedValues = HexValues(1, prime_start_pos, 1, 0) # magic starting "previous" values
end_value = start_value + nvalues
hfile = compute_hex_positions(start_value, end_value, linkedValues, save_opts)
logger.info("save info: {}".format(save_opts))
self.compute_next_chunks(hfile, nvalues, nchunks - 1, save_opts)
def test_generate_n_primes():
assert primesieve.generate_n_primes(7) == [2, 3, 5, 7, 11, 13, 17]
def test_generate_n_primes():
assert primesieve.generate_n_primes(7) == [2,3,5,7,11,13,17]
assert primesieve.generate_n_primes(5, 100) == [101,103,107,109,113]
def test_generate_n_primes():
assert primesieve.generate_n_primes(7) == [2,3,5,7,11,13,17]
def is_prime(num):
if primesieve.generate_n_primes(1, num)[0] == num:
pass
else :
return False
return True
def is_prime(num):
if primesieve.generate_n_primes(1, num)[0] == num:
pass
else:
return False
return True
