text: 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_21 (population_per_km²__2009_ INTEGER, province VARCHAR, area__km²_ VARCHAR)
  ### Question:
  What is the lowest Population per km² (2009) that has a Solomon Islands province, with an Area (km²) smaller than 28,400?
  ### Answer:
  SELECT MIN(population_per_km²__2009_) FROM table_name_21 WHERE province = "solomon islands" AND area__km²_ < 28 OFFSET 400