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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 5 |
| 7 | 35 |
| 8 | 35 |
| 9 | 5 |
| 10 | 175 |
| 11 | 1925 |
| 12 | 175 |
| 13 | 3575 |
| 14 | 175175 |
| 15 | 875875 |
| 16 | 17875 |
| 17 | 14889875 |
| 18 | 14889875 |
| 19 | 282907625 |
| 20 | 202076875 |
| 21 | 9901766875 |
| 22 | 108919435625 |
| 23 | 4647768125 |
| 24 | 2505147019375 |
| 25 | 62628675484375 |
| 26 | 814172781296875 |
| 27 | 874514265625 |
[1,1,1,1,1,5,5,35,35,5,175,1925,175,3575,175175, 875875,17875,14889875,14889875,282907625, 202076875,9901766875,108919435625,4647768125, 2505147019375,62628675484375,814172781296875, 874514265625] |