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| n | a(n) |
|---|---|
| 8 | 1 |
| 9 | 0 |
| 10 | 9 |
| 11 | 9 |
| 12 | 54 |
| 13 | 99 |
| 14 | 309 |
| 15 | 684 |
| 16 | 1720 |
| 17 | 3918 |
| 18 | 9081 |
| 19 | 20343 |
| 20 | 45261 |
| 21 | 99063 |
| 22 | 214719 |
| 23 | 460428 |
| 24 | 965980 |
| 25 | 2040096 |
| 26 | 4255851 |
| 27 | 8706522 |
| 28 | 17810088 |
| 29 | 36275538 |
| 30 | 73017027 |
| 31 | 145692324 |
| 32 | 289702678 |
| 33 | 573412764 |
| 34 | 1124242476 |
| 35 | 2191850439 |
| 36 | 4259718588 |
| 37 | 8229423030 |
| 38 | 15785908575 |
| 39 | 30199934205 |
[1,0,9,9,54,99,309,684,1720,3918,9081,20343,45261, 99063,214719,460428,965980,2040096,4255851, 8706522,17810088,36275538,73017027,145692324, 289702678,573412764,1124242476,2191850439, 4259718588,8229423030,15785908575,30199934205] |