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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 9 |
| 3 | 84 |
| 4 | 474 |
| 5 | 2325 |
| 6 | 8468 |
| 7 | 28778 |
| 8 | 79670 |
| 9 | 212049 |
| 10 | 484180 |
| 11 | 1100299 |
| 12 | 2210931 |
| 13 | 4457004 |
| 14 | 8097649 |
| 15 | 15007266 |
| 16 | 25353330 |
| 17 | 43846972 |
| 18 | 69637926 |
| 19 | 114422914 |
| 20 | 173562451 |
| 21 | 272208103 |
| 22 | 396802048 |
| 23 | 601571401 |
| 24 | 847452462 |
| 25 | 1246173200 |
| 26 | 1706973960 |
[0,9,84,474,2325,8468,28778,79670,212049,484180, 1100299,2210931,4457004,8097649,15007266,25353330, 43846972,69637926,114422914,173562451,272208103, 396802048,601571401,847452462,1246173200, 1706973960] |