What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_13, if x_13 were a writer, then x_13 is playing a game. For all x_13, x_13 is a mechanic if and only if x_13 will play a game. There is at least one x_13 for which x_13 is a janitor if and only if x_13 will play a game. For all x_13, x_13 is not a mechanic. For all x_13, if x_13 were a mechanic, then x_13 is a writer.
For all x_13, if x_13 were a mechanic, then x_13 is playing a game. For all x_13, if x_13 were a mechanic, then x_13 is playing a game. There is at least one x_13 for which if x_13 were a janitor, then x_13 is playing a game. For all x_13, if x_13 plays a game, then x_13 is a mechanic. There is at least one x_13 for which if x_13 plays a game, then x_13 is a janitor. For all x_13, x_13 will not play a game.