What is the sum of the weeks during which the Redskins played against the Houston Oilers and had more than 54,582 fans in attendance?
CREATE TABLE "schedule" (
  "week" real,
  "date" text,
  "opponent" text,
  "result" text,
  "attendance" real
);
SELECT SUM("week") FROM "schedule" WHERE "opponent"='houston oilers' AND "attendance">'54,582';