Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_21501518_1 (week__number VARCHAR, theme VARCHAR)
### Question:
Which week is the theme n/a
### Answer:
SELECT week__number FROM table_21501518_1 WHERE theme = "N/A"