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%I #12 Aug 28 2019 14:49:12
%S 4,1191,2340,4915,8101,8703,13937,13952,14029,14041,25111,25127,26062,
%T 26203,26324,26479,26490,27934,28077,28195,50506,50536,52216,52359,
%U 52892,55703,55957,56030,56059,56075,56178,56244,56566,56577,74747,75877,75952,75996,80752,80764,80765
%N Hash Parker numbers: Integers whose real 32nd root's first six nonzero digits (after the decimal point) rearranged in ascending order are equal to 234477.
%H Matt Parker's YouTube Video, <a href="https://www.youtube.com/watch?v=SOgn6J12NWE">The A4 Paper Puzzle</a>
%e 4^(1/32) = 1.0442737824274138...
%e Rearranging 442737 in ascending order gives 234477.
%e 1191^(1/32) = 1.2477346... -> 247734 -> 234477;
%e 2340^(1/32) = 1.2743478... -> 274347 -> 234477.
%o (Haskell)
%o import Data.List
%o hash :: Double -> Inthash = read . sort . take 6 . filter (/='0') . drop 1 . dropWhile (/='.') . show . (** 0.03125)
%o main :: IO ()main = print $ map (floor . fst) . filter ((==234477) . snd) $ map (\x -> (x, hash x)) [2..1000000]
%K nonn,base
%O 1,1
%A _Dan Dart_, Aug 25 2019
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