CREATE TABLE table_203_397 (id DECIMAL, "series" TEXT, "launch date" TEXT, "finale date" TEXT, "days" DECIMAL, "housemates" DECIMAL, "winner" TEXT, "main presenter" TEXT, "grand prize" TEXT, "liveshow\ audience\ millions" DECIMAL)

which season had the least amount of housemates ?
SELECT "series" FROM table_203_397 ORDER BY "housemates" LIMIT 1
SELECT "series" FROM "table_203_397" ORDER BY "housemates" NULLS FIRST LIMIT 1