CREATE TABLE table_17678 ("Character" CLOB, "Portrayed by" CLOB, "Main cast seasons" CLOB, "Recurring cast seasons" CLOB, "# of episodes" FLOAT)

What seasons does Nick lucas appear?
SELECT "Main cast seasons" FROM table_17678 WHERE "Character" = 'Nick Lucas'
SELECT "Main cast seasons" FROM "table_17678" WHERE "Character" = 'Nick Lucas'