CREATE TABLE table_33797 ("Week" FLOAT, "Date" TEXT, "Opponent" TEXT, "Result" TEXT, "Attendance" FLOAT)

Who did the Browns play on October 13, 1968?
SELECT "Opponent" FROM table_33797 WHERE "Date" = 'october 13, 1968'
SELECT "Opponent" FROM "table_33797" WHERE "Date" = 'october 13, 1968'