1 files changed, 39 insertions, 0 deletions
diff --git a/src/projecteuler/058.py b/src/projecteuler/058.py
new file mode 100644
index 0000000..a483fac
--- /dev/null
+++ b/src/projecteuler/058.py
@@ -0,0 +1,39 @@
+from common import sieve
+
+primes = sieve(30000).primes()
+prime_list = list(primes)
+prime_list.sort()
+
+def is_prime(n):
+	if n in primes:
+		return True
+	for p in prime_list:
+		if p*p > n:
+			return True
+		if n % p == 0:
+			return False
+	return True
+
+def count_primes(numbers):
+	prime = 0
+	for n in numbers:
+		if is_prime(n):
+			prime += 1
+	return prime
+
+#numbers = [1, 3, 5, 7, 9]
+prime_count = 3
+number_count = 5
+level = 2
+last = 9
+
+while 10*prime_count >= number_count:
+	step = 2 * level
+	numbers = [last+step, last+2*step, last+3*step, last+4*step]
+	prime_count += count_primes(numbers)
+	number_count += 4
+	level += 1
+	last += 4*step
+
+print 2*(level-1) + 1
+