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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 | 3909 |
| 18 | 9036 |
| 19 | 20178 |
| 20 | 44676 |
| 21 | 97191 |
| 22 | 209151 |
| 23 | 444498 |
| 24 | 935002 |
| 25 | 1947729 |
| 26 | 4021429 |
| 27 | 8234244 |
| 28 | 16732173 |
| 29 | 33758283 |
| 30 | 67656843 |
| 31 | 134751630 |
| 32 | 266817214 |
| 33 | 525411981 |
| 34 | 1029271671 |
| 35 | 2006453683 |
| 36 | 3893241810 |
| 37 | 7521104292 |
| 38 | 14468931402 |
| 39 | 27724579185 |
[1,0,9,9,54,99,309,684,1720,3909,9036,20178,44676, 97191,209151,444498,935002,1947729,4021429, 8234244,16732173,33758283,67656843,134751630, 266817214,525411981,1029271671,2006453683, 3893241810,7521104292,14468931402,27724579185] |