Was M3 produced by a person that was influenced by M1 and was influenced by M2
SELECT count(*) WHERE {
?x0 a ns:people.person .
?x0 ns:influence.influence_node.influenced_by M1 .
?x0 ns:influence.influence_node.influenced_by M2 .
M3 ns:film.film.produced_by|ns:film.film.production_companies ?x0
}