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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 17 |
| 2 | 170 |
| 3 | 1275 |
| 4 | 7905 |
| 5 | 42619 |
| 6 | 206091 |
| 7 | 912475 |
| 8 | 3753600 |
| 9 | 14503040 |
| 10 | 53073898 |
| 11 | 185172670 |
| 12 | 619237835 |
| 13 | 1993524975 |
| 14 | 6200890505 |
| 15 | 18693654410 |
| 16 | 54763023032 |
| 17 | 156250892610 |
| 18 | 435071511875 |
| 19 | 1184288668525 |
| 20 | 3156320339542 |
| 21 | 8247548150893 |
| 22 | 21155326555195 |
| 23 | 53326448236250 |
[1,17,170,1275,7905,42619,206091,912475,3753600, 14503040,53073898,185172670,619237835,1993524975, 6200890505,18693654410,54763023032,156250892610, 435071511875,1184288668525,3156320339542, 8247548150893,21155326555195,53326448236250] |