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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 17 |
| 3 | 98 |
| 4 | 498 |
| 5 | 2419 |
| 6 | 12173 |
| 7 | 56974 |
| 8 | 262287 |
| 9 | 1170434 |
| 10 | 5130110 |
| 11 | 22005641 |
| 12 | 92776584 |
| 13 | 384372350 |
| 14 | 1568795222 |
| 15 | 6311075226 |
| 16 | 25055939165 |
| 17 | 98238723797 |
| 18 | 380712713628 |
| 19 | 1459221817435 |
| 20 | 5535228002259 |
| 21 | 20790644132178 |
| 22 | 77364177052864 |
| 23 | 285327924675416 |
[1,1,17,98,498,2419,12173,56974,262287,1170434, 5130110,22005641,92776584,384372350,1568795222, 6311075226,25055939165,98238723797,380712713628, 1459221817435,5535228002259,20790644132178, 77364177052864,285327924675416] |