user: Question: Which Week has an Attendance smaller than 70056, and an Opponent of at minnesota vikings?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Record', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'September 15, 1974', 'Dallas Cowboys', 'L 0-24', '0-1', 52322.0]
SQL:

assistant: SELECT "Week" FROM "Table" WHERE "Attendance" < 70056.0 AND "Opponent" = 'at minnesota vikings';