main = do
  [n,l] <- map read . words <$> getLine
  print (kamo n l)

kamo n l = sum $ map (\p -> l - p * (n-1) + 1) (takeWhile (<= (div l (n-1))) primes)

primes :: Integral a => [a]
primes = 2 : 3 : [x | i <- [1 ..], j <- [-1, 1], let x = 6 * i + j, isPrime x]
  where
    isPrime n = null [i | i <- takeWhile (\p -> p * p <= n) primes, mod n i == 0]