Was a sequel of M0 edited by and written by a writer of M1 and M2
SELECT count(*) WHERE {
?x0 ns:film.film.edited_by ?x1 .
?x0 ns:film.film.prequel M0 .
?x0 ns:film.film.written_by ?x1 .
?x1 ns:film.writer.film M1 .
?x1 ns:film.writer.film M2
}