import Control.Applicative
import Text.Printf

main = do
  [sn, sp] <- words <$> getLine
  let 
    n = (read :: String -> Int) sn
    p = (read :: String -> Double) sp
    in
   print $ solve n p
    
solve :: Int -> Double -> Double   
solve n p = solve_ 2 [1.0,1.0 ..]
  where
    solve_ :: Int -> [Double] -> Double
    solve_ i (x:xs)
      | i == n = x
      | otherwise = (+x) $ solve_ (i+1) $ app (\y->y*(1.0 - p)) (i+1) i xs
    app :: (Double -> Double) -> Int -> Int -> [Double] -> [Double]
    app f i m ys@(x:xs) 
      | i > n = ys
      | otherwise = if i `mod` m == 0
                    then (f x) : app f (i+1) m xs
                    else x: app f (i+1) m xs