import qualified Data.ByteString.Char8 as B
import Data.Maybe
import Data.Functor

readInts :: B.ByteString -> [Int]
readInts x = fst <$> mapMaybe B.readInt (B.words x)

getParams :: B.ByteString -> (Int, Int)
getParams x = (x' !! 0, x' !! 1)
  where x' = readInts x

primes :: Int -> Double -> [(Double, Int)]
primes n p = sieve (zip (replicate n 1.0) [2..n])
  where
    sieve ((l, x):xs) = (l, x) : sieve ([((erase y x) * k, y) | (k, y) <- xs])
    sieve [] = []
    erase x y = if x `mod` y == 0 then 1 - p else 1

main =
  do
    l <- words <$> getLine
    let n = read (l !! 0) :: Int
        p = read (l !! 1) :: Double
        k = primes n p
    (putStrLn . show) (foldr (\ (v, _) r -> v + r) 0.0 k)