Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_27734577_13 ( series VARCHAR, high_rebounds VARCHAR )

### Question ###
What is the series number when al horford (10) had the high rebounds?

### Accurate SQL ###

SELECT series FROM table_27734577_13 WHERE high_rebounds = "Al Horford (10)"