Surprisingly there are only three numbers that can be written as the sum of fourth powers of their digits:

1634 = 14 + 64 + 34 + 44

8208 = 84 + 24 + 04 + 84

9474 = 94 + 44 + 74 + 44

As 1 = 14 is not a sum it is not included.

The sum of these numbers is 1634 + 8208 + 9474 = 19316.

Find the sum of all the numbers that can be written as the sum of fifth powers of their digits.

import Data.Char
p028 = (flip (-)1).sum$[read b|b <- a 6, read b ==(sum.map((^5).digitToInt))b]
where a  = [[]]
a (n+1) =[x:xs| x <-"0123456789", xs <- a n]
main = print p028

これで十分だ。

sum [x | x <- [2..1000000], x == (sum . map ((^5) . digitToInt) . show) x]