def main(args):
t = [1]
for i in range(10):
t.append(t[-1]*10)
prime = PrimeNumberPool()
ts1 = time.time()
if args.test:
max_r = t[9]
for i in range(t[4]*1):
prime.NewPrime()
else:
max_r = t[10]
for i in range(t[4]*3):
prime.NewPrime()
ts2 = time.time()
logger.debug("prepare primes takes {}s".format(ts2-ts1))
for i in range(len(prime.numbers)):
if (i%2==1): continue
p2 = prime.numbers[i]*prime.numbers[i]
remainder = 2*(i+1)*prime.numbers[i] % p2
if (remainder > max_r):
logger.debug((i+1, prime.numbers[i], remainder))
break
answer = i+1
logger.info("answer: {}".format(answer))
def main(args):
prime = PrimeNumberPool()
r = 1000
for i in range(r):
prime.NewPrime()
pb = []
for b in prime.numbers:
if (b < r):
pb.append(b)
pb.append(-b)
pb.sort()
max_cp = 30
ab = []
for a in range(-r, r):
for b in pb:
cp = cprime(a,b, prime)
if (cp > max_cp):
max_cp = cp
ab = [a,b]
logging.info(ab)
logging.info(ab[0]*ab[1])
def main(args):
prime = PrimeNumberPool()
for i in range(10000):
prime.NewPrime()
prime_num4 = []
for p in prime.numbers:
if (p > 1000 and p < 10000):
prime_num4.append(p)
pn4_perm = {}
pn4_ps = set()
for i in range(len(prime_num4) - 1):
p = prime_num4[i]
if (p in pn4_ps):
continue
for j in range(i + 1, len(prime_num4)):
q = prime_num4[j]
if (q in pn4_ps):
continue
if (IsPermute(p, q)):
pn4_ps.add(p)
pn4_ps.add(q)
if (p in pn4_perm):
pn4_perm[p].append(q)
else:
pn4_perm[p] = [p, q]
for p in list(pn4_perm.keys()):
ps = pn4_perm[p]
if (len(ps) < 3):
continue
if (IsArithSeq3(ps)):
logging.info(ps)
logging.info(IsArithSeq3(ps))
def main(args):
prime = PrimeNumberPool()
for i in range(80000):
prime.NewPrime()
all_prime = set(prime.numbers)
truncatable_prime = []
for p in all_prime:
if (p < 11):
continue
if (is_tr_prime(p, all_prime)):
truncatable_prime.append(p)
logging.debug(truncatable_prime)
logging.info(sum(truncatable_prime))
def main(args):
prime = PrimeNumberPool()
cprime = set()
ts1 = time.time()
m = 2000
for i in range(m):
prime.NewPrime()
pm = prime.numbers[:m]
ts2 = time.time()
logging.debug("time for build primes {}".format(ts2 - ts1))
for i in range(m):
p1 = pm[i]
for j in range(i, m):
p2 = pm[j]
if (not prime.IsPrime(CatNum(p1, p2))):
continue
if (not prime.IsPrime(CatNum(p2, p1))):
continue
cprime.add((p1, p2))
logging.debug(len(cprime))
ts3 = time.time()
logging.debug("time for build prime pairs {}".format(ts3 - ts2))
for (p1, p2) in cprime:
for p3 in pm:
if (p3 <= p2): continue
if (not Check(p3, [p1, p2], cprime)): continue
for p4 in pm:
if (p4 <= p3): continue
if (not Check(p4, [p1, p2, p3], cprime)): continue
for p5 in pm:
if (p5 <= p4): continue
if (not Check(p5, [p1, p2, p3, p4], cprime)): continue
logging.info((p1, p2, p3, p4, p5))
logging.info("result: {}".format(sum([p1, p2, p3, p4,
p5])))
return 0
def main(args):
description = '''
10001st prime
Problem 7
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.
What is the 10 001st prime number?
'''
primes = PrimeNumberPool()
if args.test:
logging.info('Running test...')
idx = 6 - 1
else:
idx = 10001 - 1
num_primes = primes.NumberOfPrimes()
for i in range(idx + 1 - num_primes):
primes.NewPrime()
result = primes.numbers[idx]
solution = 'result: {}'.format(result)
logging.info(solution)