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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 7 |
| 5 | 30 |
| 6 | 113 |
| 7 | 442 |
| 8 | 1692 |
| 9 | 6542 |
| 10 | 25213 |
| 11 | 97548 |
| 12 | 377617 |
| 13 | 1465010 |
| 14 | 5690787 |
| 15 | 22140830 |
| 16 | 86250091 |
| 17 | 336416094 |
| 18 | 1313641661 |
| 19 | 5134950280 |
| 20 | 20091508863 |
| 21 | 78682553016 |
| 22 | 308392187964 |
| 23 | 1209658474836 |
| 24 | 4748241492783 |
| 25 | 18650595931506 |
[1,2,2,7,30,113,442,1692,6542,25213,97548,377617, 1465010,5690787,22140830,86250091,336416094, 1313641661,5134950280,20091508863,78682553016, 308392187964,1209658474836,4748241492783, 18650595931506] |