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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 8 |
| 7 | 30 |
| 8 | 114 |
| 9 | 411 |
| 10 | 1462 |
| 11 | 5237 |
| 12 | 18998 |
| 13 | 70220 |
| 14 | 265010 |
| 15 | 1024692 |
| 16 | 4059100 |
| 17 | 16504058 |
| 18 | 68843340 |
| 19 | 294854550 |
| 20 | 1295771712 |
| 21 | 5843980456 |
| 22 | 27026394156 |
| 23 | 128135282356 |
| 24 | 622230803212 |
| 25 | 3093321051636 |
| 26 | 15728089431744 |
| 27 | 81739630155456 |
| 28 | 433801710925696 |
| 29 | 2349410730317456 |
[1,8,30,114,411,1462,5237,18998,70220,265010, 1024692,4059100,16504058,68843340,294854550, 1295771712,5843980456,27026394156,128135282356, 622230803212,3093321051636,15728089431744, 81739630155456,433801710925696,2349410730317456] |