Was a person influenced by a person , influenced by a person , and influenced by M1
SELECT count(*) WHERE {
?x0 a ns:people.person .
?x0 ns:influence.influence_node.influenced_by ?x1 .
?x0 ns:influence.influence_node.influenced_by ?x2 .
?x0 ns:influence.influence_node.influenced_by M1 .
?x1 a ns:people.person .
?x2 a ns:people.person
}