17 lines
468 B
Haskell
17 lines
468 B
Haskell
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sylvester :: [Integer]
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sylvester = map s [0 ..]
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where
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s 0 = 2
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s n = succ $ foldr ((*) . s) 1 [0 .. pred n]
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main :: IO ()
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main = do
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putStrLn "First 10 elements of Sylvester's sequence:"
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putStr $ unlines $ map show $ take 10 sylvester
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putStr "\nSum of reciprocals by sum over map: "
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print $ sum $ map ((1 /) . fromInteger) $ take 10 sylvester
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putStr "Sum of reciprocals by fold: "
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print $ foldr ((+) . (1 /) . fromInteger) 0 $ take 10 sylvester
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