Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Week | Date | Opponent | Result | Attendance |
| --- | --- | --- | --- | --- |
| 1.0 | September 2, 1979 | at New Orleans Saints | W 40-34 | 70940.0 |
| 2.0 | September 10, 1979 | at Philadelphia Eagles | W 14-10 | 66935.0 |
| 3.0 | September 16, 1979 | Denver Broncos | L 20-17 | 57677.0 |
| 4.0 | September 23, 1979 | at Detroit Lions | L 24-23 | 56249.0 |
| 5.0 | September 30, 1979 | Washington Redskins | L 16-7 | 56819.0 |
| 6.0 | October 7, 1979 | Green Bay Packers | W 25-7 | 56184.0 |
| 7.0 | October 14, 1979 | at Oakland Raiders | L 50-19 | 52900.0 |
| 8.0 | October 21, 1979 | at San Francisco 49ers | L 20-15 | 33952.0 |
| 9.0 | October 29, 1979 | Seattle Seahawks | L 31-28 | 52566.0 |
| 10.0 | November 4, 1979 | Tampa Bay Buccaneers | W 17-14 | 55150.0 |
| 11.0 | November 11, 1979 | at New York Giants | L 24-3 | 60860.0 |
| 12.0 | November 19, 1979 | at Los Angeles Rams | L 20-14 | 54097.0 |
| 13.0 | November 25, 1979 | New Orleans Saints | L 37-6 | 42815.0 |
| 14.0 | December 2, 1979 | at San Diego Chargers | W 28-26 | 50198.0 |
| 15.0 | December 9, 1979 | Los Angeles Rams | L 34-13 | 49236.0 |
| 16.0 | December 16, 1979 | San Francisco 49ers | W 31-21 | 37211.0 |
Question:
What is the week with w 31-21 result?
Answer:
16.0