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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 9 |
| 3 | 70 |
| 4 | 395 |
| 5 | 1984 |
| 6 | 9429 |
| 7 | 43434 |
| 8 | 196095 |
| 9 | 872788 |
| 10 | 3842729 |
| 11 | 16773118 |
| 12 | 72693075 |
| 13 | 313158312 |
| 14 | 1342144509 |
| 15 | 5726557522 |
| 16 | 24338016935 |
| 17 | 103078952956 |
| 18 | 435222828369 |
| 19 | 1832518331046 |
| 20 | 7696579297275 |
| 21 | 32252336887120 |
| 22 | 134873417951909 |
[0,9,70,395,1984,9429,43434,196095,872788,3842729, 16773118,72693075,313158312,1342144509,5726557522, 24338016935,103078952956,435222828369, 1832518331046,7696579297275,32252336887120, 134873417951909] |