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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 34 |
| 5 | 131 |
| 6 | 542 |
| 7 | 2297 |
| 8 | 10043 |
| 9 | 44722 |
| 10 | 202669 |
| 11 | 930527 |
| 12 | 4321859 |
| 13 | 20264186 |
| 14 | 95802300 |
| 15 | 456152409 |
| 16 | 2185541010 |
| 17 | 10529301243 |
| 18 | 50976432986 |
| 19 | 247881491762 |
| 20 | 1210135732693 |
| 21 | 5928928117319 |
| 22 | 29142693939368 |
| 23 | 143671971795711 |
[1,1,3,9,34,131,542,2297,10043,44722,202669, 930527,4321859,20264186,95802300,456152409, 2185541010,10529301243,50976432986,247881491762, 1210135732693,5928928117319,29142693939368, 143671971795711] |