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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 55 |
| 4 | 263 |
| 5 | 1196 |
| 6 | 5850 |
| 7 | 27528 |
| 8 | 135726 |
| 9 | 650470 |
| 10 | 3222016 |
| 11 | 15609182 |
| 12 | 77539788 |
| 13 | 378324161 |
| 14 | 1882662003 |
| 15 | 9231694688 |
| 16 | 45993117480 |
| 17 | 226350480727 |
| 18 | 1128618140674 |
| 19 | 5569574647042 |
| 20 | 27787141854434 |
| 21 | 137415451974877 |
| 22 | 685877545678394 |
| 23 | 3397519340596185 |
| 24 | 16963524419041184 |
| 25 | 84141927427400882 |
[1,3,13,55,263,1196,5850,27528,135726,650470, 3222016,15609182,77539788,378324161,1882662003, 9231694688,45993117480,226350480727,1128618140674, 5569574647042,27787141854434,137415451974877, 685877545678394,3397519340596185, 16963524419041184,84141927427400882] |