from euler import primesieve print sum(primesieve(2*10**6))
from euler import primesieve
def circular(n):
'''
Return a list of n rotation
'''
s = str(n)
return [int(s[i:] + s[:i]) for i in range(len(s))]
def f(n):
# filter out all primes > 10 and containing 024568
if n < 10:
return True
s = str(n)
for each in '024568':
if each in s:
return False
else:
return True
def iscircularprime(n):
return all(each in primes for each in circular(n))
primes = [x for x in primesieve(10**6) if f(x)]
print sum(iscircularprime(x) for x in primes)
from euler import primesieve
def circular(n):
'''
Return a list of n rotation
'''
s = str(n)
return [int(s[i:] + s[:i]) for i in range(len(s))]
def f(n):
# filter out all primes > 10 and containing 024568
if n < 10:
return True
s = str(n)
for each in '024568':
if each in s:
return False
else:
return True
def iscircularprime(n):
return all(each in primes for each in circular(n))
primes = [x for x in primesieve(10**6) if f(x)]
print sum(iscircularprime(x) for x in primes)
'''
a special permutation
ls = [a, b, c, d, e] # in asc order
produce:
abc abd abe acd ace ade
bcd bce bde
cde
'''
for i in range(len(ls)):
for j in range(i+1, len(ls)):
for k in range(j+1, len(ls)):
yield [ls[i], ls[j], ls[k]]
from euler import primesieve, isarithmetic
s = set(primesieve(10000)) - set(primesieve(1000))
d = {}
for each in sorted(s):
digits = tuple(sorted(map(int,str(each))))
if digits in d:
d[digits].append(each)
else:
d[digits] = [each]
for digits in sorted(d):
if len(d[digits]) >= 3:
for each in triple(d[digits]):
if isarithmetic(each):
print each
curr = 0
elif (curr % a == 0):
primefactors.add(a)
curr = curr / a
i = 0
else:
i+=1
a = primelist[i]
if (n not in primefactormap):
primefactormap[n] = primefactors;
return primefactors;
#create prime list
primes = euler.primesieve(1000001)
primelist = []
for i in range(0,len(primes)):
if primes[i]:
primelist.append(i)
now = datetime.datetime.now()
print ("Starttime - " + str(now))
max_pn = 0
max_n = 0
n_pn = 0
for n in range(2,1000001):
if (n % 10000 == 0):
print(n)
from euler import primesieve
'''
f(n) = n*n + a*n + b
when n = 0, b must be a prime. And |b| < 1000, so b is one of the primes <
1000.
'''
primes = set(primesieve(10**5))
def allprimes(n, a, b):
''' True if f(n, a, b) is prime for n in [0...n) '''
ls = [n*n + a*n + b for n in range(n)]
largest = max(ls)
if largest < 10**5:
return all(l in primes for l in ls)
else:
raise Exception('Prime set not big enough. Max value %d' % largest)
from itertools import *
def mostprimes(a, b):
''' count how many primes for consecutive values of n '''
for n in count():
f = n*n + a*n + b
if f not in primes:
break
return n
prime1k = primesieve(1000)
from euler import primesieve
MAX = 1000000
p1m = primesieve(MAX)
p1ms = set(p1m)
l = len(p1m)
def maxchainlen(MAX):
# longest chain of consequtive primes that sums < MAX
s = 0
for i in range(l):
s += p1m[i]
if not s < MAX:
return i
def find():
mcl = maxchainlen(MAX)
for chainlen in range(mcl, 0, -1):
for i in range(l - chainlen):
s = sum(p1m[i:i + chainlen])
if s >= MAX:
break
if s in p1ms:
return s
print find()
from euler import primesieve print sum(primesieve(2 * 10**6))
from euler import primesieve
MAX = 1000000
p1m = primesieve(MAX)
p1ms= set(p1m)
l = len(p1m)
def maxchainlen(MAX):
# longest chain of consequtive primes that sums < MAX
s = 0
for i in range(l):
s += p1m[i]
if not s < MAX:
return i
def find():
mcl = maxchainlen(MAX)
for chainlen in range(mcl, 0, -1):
for i in range(l-chainlen):
s = sum(p1m[i:i+chainlen])
if s >= MAX:
break
if s in p1ms:
return s
print find()
from euler import primesieve
'''
f(n) = n*n + a*n + b
when n = 0, b must be a prime. And |b| < 1000, so b is one of the primes <
1000.
'''
primes = set(primesieve(10**5))
def allprimes(n, a, b):
''' True if f(n, a, b) is prime for n in [0...n) '''
ls = [n * n + a * n + b for n in range(n)]
largest = max(ls)
if largest < 10**5:
return all(l in primes for l in ls)
else:
raise Exception('Prime set not big enough. Max value %d' % largest)
from itertools import *
def mostprimes(a, b):
''' count how many primes for consecutive values of n '''
for n in count():
f = n * n + a * n + b
if f not in primes:
break
