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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 51 |
| 3 | 257 |
| 4 | 1181 |
| 5 | 4825 |
| 6 | 18307 |
| 7 | 64013 |
| 8 | 209366 |
| 9 | 645067 |
| 10 | 1889163 |
| 11 | 5290881 |
| 12 | 14255341 |
| 13 | 37123088 |
| 14 | 93794323 |
| 15 | 230612423 |
| 16 | 553103591 |
| 17 | 1296531617 |
| 18 | 2974976604 |
| 19 | 6690386564 |
| 20 | 14761551146 |
| 21 | 31981485566 |
| 22 | 68087935696 |
| 23 | 142536873665 |
| 24 | 293578073240 |
[8,51,257,1181,4825,18307,64013,209366,645067, 1889163,5290881,14255341,37123088,93794323, 230612423,553103591,1296531617,2974976604, 6690386564,14761551146,31981485566,68087935696, 142536873665,293578073240] |