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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 22 |
| 3 | 101 |
| 4 | 457 |
| 5 | 2078 |
| 6 | 9433 |
| 7 | 42845 |
| 8 | 194566 |
| 9 | 883613 |
| 10 | 4012801 |
| 11 | 18223694 |
| 12 | 82760689 |
| 13 | 375847925 |
| 14 | 1706868598 |
| 15 | 7751541269 |
| 16 | 35202703993 |
| 17 | 159868900862 |
| 18 | 726025630537 |
| 19 | 3297159197645 |
| 20 | 14973657006694 |
| 21 | 68001085403597 |
| 22 | 308818855257649 |
[1,5,22,101,457,2078,9433,42845,194566,883613, 4012801,18223694,82760689,375847925,1706868598, 7751541269,35202703993,159868900862,726025630537, 3297159197645,14973657006694,68001085403597, 308818855257649] |