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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 13 |
| 7 | 31 |
| 8 | 63 |
| 9 | 141 |
| 10 | 293 |
| 11 | 665 |
| 12 | 1553 |
| 13 | 3795 |
| 14 | 9225 |
| 15 | 22257 |
| 16 | 53623 |
| 17 | 132277 |
| 18 | 321651 |
| 19 | 786553 |
| 20 | 1928565 |
| 21 | 4806503 |
| 22 | 11885969 |
| 23 | 29498995 |
| 24 | 73362933 |
| 25 | 184210629 |
| 26 | 460165983 |
| 27 | 1151961103 |
[1,1,1,1,5,13,31,63,141,293,665,1553,3795,9225, 22257,53623,132277,321651,786553,1928565,4806503, 11885969,29498995,73362933,184210629,460165983, 1151961103] |