import Control.Applicative ((<$>))

countFactors :: Int -> Int
countFactors n = length [f | f <- [1 .. n], mod n f == 0]

prob :: Double -> Int -> Double
prob p n = (1 - p) ** (fromIntegral $ countFactors n - 2)

main :: IO ()
main = do
    (n : p : _) <- words <$> getLine
    print $ sum $ map (prob $ read p) [2 .. read n]