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_name_51 (image INTEGER, harrison VARCHAR, ashmolean VARCHAR)
### Question:
What is the lowest image with a 20w Harrison, and less than 20 for Ashmolean?
### Answer:
SELECT MIN(image) FROM table_name_51 WHERE harrison = "20w" AND ashmolean < 20