Was M1 's sequel 's producer 's employer M0 's country of nationality
SELECT count(*) WHERE {
?x0 ^ns:people.person.nationality M0 .
?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
?x1 ns:film.producer.film|ns:film.production_company.films ?x2 .
?x2 ns:film.film.prequel M1
}