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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 16 |
| 5 | 37 |
| 6 | 86 |
| 7 | 200 |
| 8 | 465 |
| 9 | 1081 |
| 10 | 2513 |
| 11 | 5842 |
| 12 | 13581 |
| 13 | 31572 |
| 14 | 73396 |
| 15 | 170625 |
| 16 | 396655 |
| 17 | 922111 |
| 18 | 2143648 |
| 19 | 4983377 |
| 20 | 11584946 |
| 21 | 26931732 |
| 22 | 62608681 |
| 23 | 145547525 |
| 24 | 338356945 |
| 25 | 786584466 |
| 26 | 1828587033 |
| 27 | 4250949112 |
| 28 | 9882257736 |
| 29 | 22973462017 |
| 30 | 53406819691 |
[1,3,7,16,37,86,200,465,1081,2513,5842,13581, 31572,73396,170625,396655,922111,2143648,4983377, 11584946,26931732,62608681,145547525,338356945, 786584466,1828587033,4250949112,9882257736, 22973462017,53406819691] |