Was a sequel of M0 executive produced by and written by M1 's producer
SELECT count(*) WHERE {
?x0 ns:film.film.executive_produced_by ?x1 .
?x0 ns:film.film.prequel M0 .
?x0 ns:film.film.written_by ?x1 .
?x1 ns:film.producer.film|ns:film.production_company.films M1
}