Were M1 and M2 produced by and executive produced by a art director
SELECT count(*) WHERE {
?x0 a ns:film.film_art_director .
M1 ns:film.film.executive_produced_by ?x0 .
M1 ns:film.film.produced_by|ns:film.film.production_companies ?x0 .
M2 ns:film.film.executive_produced_by ?x0 .
M2 ns:film.film.produced_by|ns:film.film.production_companies ?x0
}