import Control.Monad

main = getLine >>= print . solve . map read . words

solve :: [Int] -> Double
solve [p, c] = fromIntegral ((sum [2, 3, 5, 7, 11, 13] ^ p) * (sum [4, 6, 8, 9, 10, 12] ^ c)) / 6.0 ^^ (p + c)