def sieve(s: Stream[Int]): Stream[Int] =
  Stream.cons(s.head, sieve(s.tail filter (_ % s.head != 0)))

val ps = sieve(Stream.from(2))

println(ps.tail.head)

$ scala e.scala 
/Users/kzfm/scala/e.scala:4: error: type mismatch;
 found   : scala.collection.immutable.Stream[scala.Int]
 required: Stream[<empty>.Int]
val ps = sieve(Stream.from(2))
                          ^
/Users/kzfm/scala/e.scala:2: error: value % is not a member of Int
  Stream.cons(s.head, sieve(s.tail filter (_ % s.head != 0)))
                                             ^
two errors found