main :: IO ()
main = interact $ show . solve . map (read :: String -> Int). words

solve :: [Int] -> Int
solve [x] = length $ filter check ys
        where
            ys = takeWhile (<= x) primes
            check :: Int -> Bool
            check n
                |  (n * n - 2) `elem` ys     = True
                | otherwise                  = False

isPrime :: Int -> Bool
isPrime 2 = True
isPrime n
    | n < 2            = False
    | (n `mod` 2) == 0 = False
    | otherwise        = testDiv 3 n
    where testDiv :: Int -> Int -> Bool
          testDiv i n
              | i * i > n      = True
              | n `mod` i == 0 = False
              | otherwise      = testDiv (i + 2) n

primes :: Integral a => [a]
primes = map fromIntegral $ [2,3] ++ primes'
    where
        primes' = [5] ++ f 1 7 primes'
        f m s (p : ps) = [n | n <- ns, gcd m n == 1] ++ f (m * p) (p * p) ps
            where
                ns = [x + y | x <- [s, s + 6.. p * p - 2], y <- [0, 4]]