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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 29 |
| 4 | 127 |
| 5 | 578 |
| 6 | 2694 |
| 7 | 12777 |
| 8 | 61311 |
| 9 | 296687 |
| 10 | 1444610 |
| 11 | 7067651 |
| 12 | 34706412 |
| 13 | 170926789 |
| 14 | 843757686 |
| 15 | 4172911941 |
| 16 | 20669327222 |
| 17 | 102509183526 |
| 18 | 508927584984 |
| 19 | 2528902166589 |
| 20 | 12575676943431 |
| 21 | 62575687839661 |
| 22 | 311540887849208 |
| 23 | 1551767773859324 |
| 24 | 7732381378091565 |
| 25 | 38543552002276177 |
| 26 | 192186472317221319 |
[1,2,7,29,127,578,2694,12777,61311,296687,1444610, 7067651,34706412,170926789,843757686,4172911941, 20669327222,102509183526,508927584984, 2528902166589,12575676943431,62575687839661, 311540887849208,1551767773859324,7732381378091565, 38543552002276177,192186472317221319] |