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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 45 |
| 4 | 187 |
| 5 | 813 |
| 6 | 3595 |
| 7 | 16129 |
| 8 | 73455 |
| 9 | 337045 |
| 10 | 1560531 |
| 11 | 7271537 |
| 12 | 34061735 |
| 13 | 160372701 |
| 14 | 757970843 |
| 15 | 3595687081 |
| 16 | 17111115759 |
| 17 | 81651588021 |
| 18 | 390627636835 |
| 19 | 1872913492353 |
| 20 | 8998295638711 |
| 21 | 43311574341005 |
| 22 | 208819980112683 |
| 23 | 1008354117957401 |
| 24 | 4876013903788671 |
| 25 | 23609343188579301 |
| 26 | 114453003449887219 |
[1,3,11,45,187,813,3595,16129,73455,337045, 1560531,7271537,34061735,160372701,757970843, 3595687081,17111115759,81651588021,390627636835, 1872913492353,8998295638711,43311574341005, 208819980112683,1008354117957401,4876013903788671, 23609343188579301,114453003449887219] |