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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 24 |
| 5 | 65 |
| 6 | 177 |
| 7 | 481 |
| 8 | 1308 |
| 9 | 3555 |
| 10 | 9664 |
| 11 | 26269 |
| 12 | 71406 |
| 13 | 194103 |
| 14 | 527625 |
| 15 | 1434235 |
| 16 | 3898654 |
| 17 | 10597641 |
| 18 | 28807374 |
| 19 | 78306562 |
| 20 | 212859305 |
| 21 | 578611580 |
| 22 | 1572829344 |
| 23 | 4275393425 |
| 24 | 11621724256 |
| 25 | 31591121861 |
| 26 | 85873572496 |
| 27 | 233428571660 |
| 28 | 634524644587 |
| 29 | 1724816811090 |
| 30 | 4688538195006 |
| 31 | 12744768177522 |
[1,1,3,9,24,65,177,481,1308,3555,9664,26269,71406, 194103,527625,1434235,3898654,10597641,28807374, 78306562,212859305,578611580,1572829344, 4275393425,11621724256,31591121861,85873572496, 233428571660,634524644587,1724816811090, 4688538195006,12744768177522] |