What dance had a score total of 31?
CREATE TABLE "table1_2803106_1" (
  "week_num" real,
  "dance_song" text,
  "horwood" text,
  "goodman" text,
  "dixon" text,
  "tonioli" text,
  "total" text,
  "result" text
);
SELECT "dance_song" FROM "table1_2803106_1" WHERE "total"='31';