def validPair(primes, maxprime, p1, p2):
x = int(p1 + p2)
y = int(p2 + p1)
if x > maxprime:
if not libeuler.isPrime(x): return False
else:
if x not in primes: return False
if y > maxprime:
if not libeuler.isPrime(y): return False
else:
if y not in primes: return False
return True
def main():
num = 1
diagprimes = 0
total = 1
x = 0
avg = 1
while avg > .1:
x += 2
for i in range(3):
num += x
total += 1
if libeuler.isPrime(num): diagprimes += 1
num += x
total += 1
avg = diagprimes / total
print(x+1)