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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 85 |
| 5 | 381 |
| 6 | 1751 |
| 7 | 8135 |
| 8 | 38173 |
| 9 | 180415 |
| 10 | 857695 |
| 11 | 4096830 |
| 12 | 19645975 |
| 13 | 94523729 |
| 14 | 456079769 |
| 15 | 2206005414 |
| 16 | 10693086637 |
| 17 | 51930129399 |
| 18 | 252617434619 |
| 19 | 1230714593340 |
| 20 | 6003931991895 |
| 21 | 29325290391416 |
| 22 | 143393190367102 |
| 23 | 701862880794183 |
| 24 | 3438561265961263 |
[1,1,5,19,85,381,1751,8135,38173,180415,857695, 4096830,19645975,94523729,456079769,2206005414, 10693086637,51930129399,252617434619, 1230714593340,6003931991895,29325290391416, 143393190367102,701862880794183,3438561265961263] |