Question: how many na -350- with title and source being bokumo sekai wo sukuitai: battle tournament
Schema: create table table_13663434_1 (na__350_ varchar, title_and_source varchar, PRIMARY KEY (na__350_))
SQL: select count(na__350_) from table_13663434_1 where title_and_source = "bokumo sekai wo sukuitai: battle tournament"