import Control.Applicative ((<$>))
import Text.Printf

main :: IO ()
main = do
    d <- solve . map read . words <$> getLine
    printf "%.9f" d

solve :: [Int] -> Double
solve [p, c] = (product $ replicate p ep)  * (product $ replicate c ec)
    where
        ep = (2 + 3 + 5 + 7 + 11 + 13) / 6
        ec = (4 + 6 + 8 + 9 + 10 + 12) / 6