eul9 s = [a*b*c | c <- [1..s], b <- [1..c], a <- [1..b], a+b+c == s, a^2 + b^2 == c^2]
eul9 s = [a*b*c | c <- [1..s], b <- [1..c], a <- [1..b], a+b+c == s, a^2 + b^2 == c^2]
eul9 s = [a*b*c | c <- [1..s], b <- [1..c], a <- [1..b], a+b+c == s, a^2 + b^2 == c^2]