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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 34 |
| 4 | 115 |
| 5 | 387 |
| 6 | 1300 |
| 7 | 4366 |
| 8 | 14665 |
| 9 | 49263 |
| 10 | 165490 |
| 11 | 555934 |
| 12 | 1867555 |
| 13 | 6273687 |
| 14 | 21075220 |
| 15 | 70798066 |
| 16 | 237832225 |
| 17 | 798950763 |
| 18 | 2683918570 |
| 19 | 9016098634 |
| 20 | 30287816995 |
| 21 | 101745987387 |
| 22 | 341795711140 |
| 23 | 1148195728966 |
| 24 | 3857138603785 |
| 25 | 12957301471863 |
| 26 | 43527515777650 |
[1,3,10,34,115,387,1300,4366,14665,49263,165490, 555934,1867555,6273687,21075220,70798066, 237832225,798950763,2683918570,9016098634, 30287816995,101745987387,341795711140, 1148195728966,3857138603785,12957301471863, 43527515777650] |