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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 4 |
| 8 | 7 |
| 9 | 18 |
| 10 | 27 |
| 11 | 60 |
| 12 | 127 |
| 13 | 520 |
| 14 | 1313 |
| 15 | 5577 |
| 16 | 14738 |
| 17 | 65753 |
| 18 | 214371 |
| 19 | 1292619 |
| 20 | 5259696 |
| 21 | 36901354 |
| 22 | 169889413 |
| 23 | 1338225681 |
| 24 | 7299428688 |
[1,1,1,1,1,1,4,7,18,27,60,127,520,1313,5577,14738, 65753,214371,1292619,5259696,36901354,169889413, 1338225681,7299428688] |