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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 7 |
| 6 | 14 |
| 7 | 31 |
| 8 | 66 |
| 9 | 141 |
| 10 | 313 |
| 11 | 702 |
| 12 | 1577 |
| 13 | 3581 |
| 14 | 8207 |
| 15 | 18903 |
| 16 | 43770 |
| 17 | 101903 |
| 18 | 238282 |
| 19 | 559322 |
| 20 | 1317717 |
| 21 | 3114676 |
| 22 | 7383914 |
| 23 | 17552857 |
| 24 | 41831618 |
| 25 | 99923471 |
| 26 | 239200459 |
| 27 | 573750288 |
| 28 | 1378763083 |
| 29 | 3319005743 |
| 30 | 8002573350 |
| 31 | 19324601494 |
| 32 | 46731582653 |
| 33 | 113160019865 |
[1,1,1,2,4,7,14,31,66,141,313,702,1577,3581,8207, 18903,43770,101903,238282,559322,1317717,3114676, 7383914,17552857,41831618,99923471,239200459, 573750288,1378763083,3319005743,8002573350, 19324601494,46731582653,113160019865] |