I'm not sure.. but if you want to do it like that, the numbers would have to increase horrizontally, not vertically. You would still get your wanted bag look though, so I'm probably just confusing you
Code:
+--+--+
| 1| 2|
+--+--+
| 3| 4|
+--+--+
| 5| 6|
+--+--+
| 7| 8|
+--+--+
| 9|10|
+--+--+
|11| |
+--+--+