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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 18 |
| 11 | 164 |
| 12 | 1050 |
| 13 | 5367 |
| 14 | 23232 |
| 15 | 88125 |
| 16 | 299992 |
| 17 | 932849 |
| 18 | 2685747 |
| 19 | 7235237 |
| 20 | 18392853 |
| 21 | 44427807 |
| 22 | 102552852 |
| 23 | 227298680 |
| 24 | 485679518 |
| 25 | 1003915611 |
| 26 | 2013360324 |
| 27 | 3927664296 |
| 28 | 7469755903 |
| 29 | 13876848040 |
| 30 | 25225619858 |
| 31 | 44939663514 |
| 32 | 78569415198 |
| 33 | 134974052794 |
| 34 | 228088973049 |
[1,18,164,1050,5367,23232,88125,299992,932849, 2685747,7235237,18392853,44427807,102552852, 227298680,485679518,1003915611,2013360324, 3927664296,7469755903,13876848040,25225619858, 44939663514,78569415198,134974052794,228088973049] |