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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 45 |
| 4 | 195 |
| 5 | 855 |
| 6 | 3859 |
| 7 | 17664 |
| 8 | 81534 |
| 9 | 380118 |
| 10 | 1785231 |
| 11 | 8421649 |
| 12 | 39941158 |
| 13 | 190204244 |
| 14 | 908487667 |
| 15 | 4353177705 |
| 16 | 20914598678 |
| 17 | 100694137234 |
| 18 | 485839187516 |
| 19 | 2348481826887 |
| 20 | 11369957309370 |
| 21 | 55131637668280 |
| 22 | 267694529100150 |
| 23 | 1301363943139225 |
| 24 | 6333801895412544 |
| 25 | 30859564496858068 |
| 26 | 150496855039572611 |
[1,3,11,45,195,855,3859,17664,81534,380118, 1785231,8421649,39941158,190204244,908487667, 4353177705,20914598678,100694137234,485839187516, 2348481826887,11369957309370,55131637668280, 267694529100150,1301363943139225,6333801895412544, 30859564496858068,150496855039572611] |