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_name_12 (week VARCHAR, opponent VARCHAR, attendance VARCHAR)

### Question ###
How many weeks have an Opponent of at san francisco 49ers, and an Attendance smaller than 34,354?

### Accurate SQL ###

SELECT COUNT(week) FROM table_name_12 WHERE opponent = "at san francisco 49ers" AND attendance < 34 OFFSET 354