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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 10 |
| 3 | 44 |
| 4 | 168 |
| 5 | 642 |
| 6 | 2463 |
| 7 | 9454 |
| 8 | 36363 |
| 9 | 139880 |
| 10 | 538092 |
| 11 | 2069817 |
| 12 | 7961603 |
| 13 | 30624506 |
| 14 | 117797841 |
| 15 | 453112757 |
| 16 | 1742910881 |
| 17 | 6704156588 |
| 18 | 25787728116 |
| 19 | 99193227204 |
| 20 | 381549556196 |
| 21 | 1467641171329 |
| 22 | 5645323318604 |
| 23 | 21714895989511 |
| 24 | 83526962265404 |
[1,10,44,168,642,2463,9454,36363,139880,538092, 2069817,7961603,30624506,117797841,453112757, 1742910881,6704156588,25787728116,99193227204, 381549556196,1467641171329,5645323318604, 21714895989511,83526962265404] |