| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 10 |
=1+（
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 4 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 8 |
| 1 |
| 9 |
| 1 |
| 10 |
=1+1+
| 1260+1008+720+630+560+504 |
| 5040 |
=2+
| 2341 |
| 2520 |
≈2.93；
1+
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 11 |
=2
| 2341 |
| 2520 |
| 1 |
| 11 |
≈3.01．
所以至少要选11个数．
故答案为：11．
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 99 |
| 1 |
| 100 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 10 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 6 |
| 1 |
| 4 |
| 1 |
| 5 |
| 1 |
| 7 |
| 1 |
| 8 |
| 1 |
| 9 |
| 1 |
| 10 |
| 1260+1008+720+630+560+504 |
| 5040 |
| 2341 |
| 2520 |
| 1 |
| 2 |
| 1 |
| 3 |
| 1 |
| 4 |
| 1 |
| 11 |
| 2341 |
| 2520 |
| 1 |
| 11 |