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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 27 |
| 5 | 114 |
| 6 | 509 |
| 7 | 2365 |
| 8 | 11318 |
| 9 | 55411 |
| 10 | 276231 |
| 11 | 1397430 |
| 12 | 7156089 |
| 13 | 37023225 |
| 14 | 193229466 |
| 15 | 1016141199 |
| 16 | 5378940051 |
| 17 | 28638955098 |
| 18 | 153267403397 |
| 19 | 824014568581 |
| 20 | 4448456379134 |
| 21 | 24104579252971 |
| 22 | 131055735586767 |
| 23 | 714741620026542 |
| 24 | 3908997981612017 |
| 25 | 21434123083817329 |
[1,2,7,27,114,509,2365,11318,55411,276231,1397430, 7156089,37023225,193229466,1016141199,5378940051, 28638955098,153267403397,824014568581, 4448456379134,24104579252971,131055735586767, 714741620026542,3908997981612017, 21434123083817329] |