Problem 49

import Number hiding (diff)
import Data.List
perm ::Eq a =>[a]->Int->[[a]]
perm _  = [[]]
perm [] _ = []
perm xs@(_:_) (n+1)=concat[map (h:)$perm(delete h xs)n|h<-xs]
get _  = [[]]
get [] _ = []
get (x:xs) (n+1) = [x:ys|ys<-get xs n]++get xs (n+1)
diff xs = zipWith (-) (tail xs) $ xs
p049 n =filter (same.diff).flip get 3.nub.sort.filter isPrime .map read. perm ns $length ns
where ns = show n
same [a,b] = a == b
main =print.filter ((==12).length.concatMap show).nub.concatMap p049 .takeWhile(<10000).dropWhile(<1000)$primes