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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 23 |
| 4 | 93 |
| 5 | 397 |
| 6 | 1743 |
| 7 | 7835 |
| 8 | 35746 |
| 9 | 165186 |
| 10 | 770599 |
| 11 | 3622718 |
| 12 | 17138997 |
| 13 | 81505690 |
| 14 | 389304925 |
| 15 | 1866373874 |
| 16 | 8976096969 |
| 17 | 43288108887 |
| 18 | 209262664063 |
| 19 | 1013747551292 |
| 20 | 4920151811424 |
| 21 | 23919322278143 |
| 22 | 116457079657159 |
| 23 | 567760445594646 |
| 24 | 2771349016260029 |
| 25 | 13542414273198623 |
| 26 | 66242681480812979 |
[1,2,6,23,93,397,1743,7835,35746,165186,770599, 3622718,17138997,81505690,389304925,1866373874, 8976096969,43288108887,209262664063,1013747551292, 4920151811424,23919322278143,116457079657159, 567760445594646,2771349016260029, 13542414273198623,66242681480812979] |