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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 79 |
| 6 | 276 |
| 7 | 936 |
| 8 | 3376 |
| 9 | 12259 |
| 10 | 45648 |
| 11 | 171739 |
| 12 | 655664 |
| 13 | 2524835 |
| 14 | 9813259 |
| 15 | 38410167 |
| 16 | 151332137 |
| 17 | 599541153 |
| 18 | 2387199083 |
| 19 | 9547195445 |
| 20 | 38335338712 |
| 21 | 154484001619 |
| 22 | 624579964260 |
| 23 | 2532713370789 |
| 24 | 10298393401623 |
| 25 | 41979975505800 |
| 26 | 171522040764060 |
[1,1,3,8,26,79,276,936,3376,12259,45648,171739, 655664,2524835,9813259,38410167,151332137, 599541153,2387199083,9547195445,38335338712, 154484001619,624579964260,2532713370789, 10298393401623,41979975505800,171522040764060] |