Which Game has an Opponent of at kansas city chiefs, and an Attendance smaller than 40,213?
CREATE TABLE "schedule" (
  "game" real,
  "date" text,
  "opponent" text,
  "result" text,
  "oilers_points" real,
  "opponents" real,
  "oilers_first_downs" real,
  "record" text,
  "attendance" real
);
SELECT SUM("game") FROM "schedule" WHERE "opponent"='at kansas city chiefs' AND "attendance"<'40,213';