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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 24 |
| 4 | 103 |
| 5 | 416 |
| 6 | 1902 |
| 7 | 8283 |
| 8 | 39070 |
| 9 | 177344 |
| 10 | 851579 |
| 11 | 3965436 |
| 12 | 19254227 |
| 13 | 91187768 |
| 14 | 446032075 |
| 15 | 2137425882 |
| 16 | 10508325562 |
| 17 | 50787684839 |
| 18 | 250604293372 |
| 19 | 1218908813784 |
| 20 | 6030763382894 |
| 21 | 29475469821857 |
| 22 | 146131936379380 |
| 23 | 716924969782732 |
| 24 | 3559893624198634 |
| 25 | 17517194768320811 |
| 26 | 87087929619336864 |
[1,2,7,24,103,416,1902,8283,39070,177344,851579, 3965436,19254227,91187768,446032075,2137425882, 10508325562,50787684839,250604293372, 1218908813784,6030763382894,29475469821857, 146131936379380,716924969782732,3559893624198634, 17517194768320811,87087929619336864] |