from tools import get_primes
import datetime
a = []
n = 1000000
#ts = datetime.datetime.now()
list_of_primes = get_primes(n)
#print datetime.datetime.now() - ts
#ts = datetime.datetime.now()
primes = set(p for p in list_of_primes)
max_sum = 0
max_len = 0
for i in range(len(list_of_primes)):
sum = 0
len = 0
while sum < list_of_primes[-1]:
sum = sum + list_of_primes[len]
len = len + 1
if len > max_len and sum in primes:
max_len = len
max_sum = sum
del list_of_primes[0]
#print datetime.datetime.now() - ts
print "Prime " + str(max_sum)
##Consider numbers t(n) of the form t(n) = 2n^2-1 with n > 1.
##The first such numbers are 7, 17, 31, 49, 71, 97, 127 and 161.
##It turns out that only 49 = 7*7 and 161 = 7*23 are not prime.
##For n 10000 there are 2202 numbers t(n) that are prime.
##
##How many numbers t(n) are prime for n 50,000,000 ?
from tools import get_primes
n = 10000
list_of_primes = get_primes(n*100)
set_of_primes = set(p for p in list_of_primes)
def t(n):
return (2*(n**2))-1
p=0
i=0
for n in range(2,n):
i+=1
## if i % 1000 == 0:
## print i
if t(n) in set_of_primes:
p+=1
print t(n)
## print "--- %d" % (n)
##print "-----"
print i
print p
from tools import get_primes
from tools import is_permutation
import datetime
a = []
n = 9999
ts = datetime.datetime.now()
list_of_primes = [prime for prime in get_primes(n) if prime > 999]
set_of_primes = set(p for p in list_of_primes)
#print "\n".join(str(p) for p in list_of_primes)
print datetime.datetime.now() - ts
ts = datetime.datetime.now()
for p1p in range(len(list_of_primes)):
p1 = list_of_primes[p1p]
for p2p in range(p1p+1, len(list_of_primes)):
p2 = list_of_primes[p2p]
p3 = (p2+(p2-p1))
if p3 in set_of_primes:
#print "p1 " + str(p1) + " p2 " + str(p2) + " (p2+(p2-p1)) " + str(p2+(p2-p1))
if is_permutation(str(p1), str(p2)) and is_permutation(str(p2), str(p3)):
print str(p1) +" "+ str(p2) +" "+ str(p3)
print datetime.datetime.now() - ts
