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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 12 |
| 6 | 28 |
| 7 | 69 |
| 8 | 182 |
| 9 | 497 |
| 10 | 1399 |
| 11 | 4028 |
| 12 | 11852 |
| 13 | 35626 |
| 14 | 109494 |
| 15 | 344338 |
| 16 | 1108565 |
| 17 | 3653536 |
| 18 | 12320940 |
| 19 | 42483305 |
| 20 | 149640000 |
| 21 | 537975261 |
| 22 | 1972713660 |
| 23 | 7374794356 |
| 24 | 28100132482 |
| 25 | 109117922021 |
| 26 | 431821675389 |
| 27 | 1741507272791 |
[1,1,2,3,6,12,28,69,182,497,1399,4028,11852,35626, 109494,344338,1108565,3653536,12320940,42483305, 149640000,537975261,1972713660,7374794356, 28100132482,109117922021,431821675389, 1741507272791] |