Beispiel #1
0
def run(target=8):
    pgen = eu.GenFinder(eu.gen_primes())

    # Loop over all prime numbers
    for prime_idx in eu.numbers():
        curr_prime = pgen[prime_idx]
        curr_digits = eu.digits(curr_prime) # digits in current prime

        # Get all selections of indices from current digits
        for rindices in eu.selections(range(len(curr_digits))):
            rzero = 0 in rindices

            if len(rindices) == 0:
                continue

            found_primes = []
            work_digs = curr_digits[:] # copy digits of current prime

            # Choose the digit which we will insert at each index in rindices (the current selection)
            for replacement in range(10):
                if replacement == 0 and rzero:
                     continue

                for rindex in rindices:
                    work_digs[rindex] = replacement

                prime_idx = pgen.find(eu.undigits(work_digs))
                if prime_idx != -1:
                    found_primes.append(pgen[prime_idx])

            if len(found_primes) >= target:
                # print "answer =",min(found_primes),found_primes,rindices
                return min(found_primes)
Beispiel #2
0
def run():
    ts = euler_util.GenFinder(twice_squares())
    primes = euler_util.GenFinder(euler_util.gen_primes())

    for i in euler_util.numbers(9, 2):
        if primes.contains(i):
            continue

        if not find_sum(i, ts, primes):
            print i
            return
Beispiel #3
0
def run():
    pgen = euler_util.gen_primes()

    # initialize primes list with single-digit primes...we don't consider those for rotation
    primes = [pgen.next(), pgen.next(), pgen.next(), pgen.next()]
    results = []

    while len(results) < 11:
        prime = pgen.next()
        primes.append(prime)
        if curious(prime, primes):
            print prime
            results.append(prime)

    print sum(results)
Beispiel #4
0
import euler_util


def f(n, a, b):
    return (n ** 2) + (a * n) + b


prime_gen = euler_util.gen_primes()
primes = [prime_gen.next() for i in range(1000)]


def count_primes(a, b):
    sum = 0
    for n in euler_util.numbers():
        val = f(n, a, b)
        while val > primes[-1]:
            primes.append(prime_gen.next())
        if not val in primes:
            return sum
        sum += 1


def run():
    max_count = 0
    max_a = 0
    max_b = 0

    for a in range(-999, 1000):
        for b in range(-999, 1000):
            count = count_primes(a, b)
            if count > max_count: