Also, this is (I think, I'm not 100% up on Scala), insanely inefficient. Usually when people discuss the n-queens problem, they do a backtrack search, stopping

Also, this is (I think, I'm not 100% up on Scala), insanely inefficient. Usually when people discuss the n-queens problem, they do a backtrack search, stopping as soon as some queen conflicts with an earlier queen. You can of course then go on and get increasingly clever, but I think you should at least aim for backtracking.