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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 39 |
| 4 | 179 |
| 5 | 838 |
| 6 | 4001 |
| 7 | 19297 |
| 8 | 93811 |
| 9 | 458470 |
| 10 | 2250074 |
| 11 | 11078274 |
| 12 | 54681991 |
| 13 | 270441626 |
| 14 | 1339657025 |
| 15 | 6644734835 |
| 16 | 32993447151 |
| 17 | 163970009088 |
| 18 | 815501935265 |
| 19 | 4058439564102 |
| 20 | 20208123550700 |
| 21 | 100668187184629 |
| 22 | 501683893890998 |
| 23 | 2501017031948005 |
| 24 | 12471894198259711 |
| 25 | 62210144249509122 |
| 26 | 310376787176283060 |
[1,2,9,39,179,838,4001,19297,93811,458470,2250074, 11078274,54681991,270441626,1339657025,6644734835, 32993447151,163970009088,815501935265, 4058439564102,20208123550700,100668187184629, 501683893890998,2501017031948005, 12471894198259711,62210144249509122, 310376787176283060] |