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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 12 |
| 7 | 28 |
| 8 | 65 |
| 9 | 155 |
| 10 | 387 |
| 11 | 1002 |
| 12 | 2641 |
| 13 | 7016 |
| 14 | 18743 |
| 15 | 50321 |
| 16 | 135608 |
| 17 | 366399 |
| 18 | 992221 |
| 19 | 2693705 |
| 20 | 7333666 |
| 21 | 20026582 |
| 22 | 54858122 |
| 23 | 150739957 |
| 24 | 415479332 |
| 25 | 1148563576 |
| 26 | 3183963911 |
| 27 | 8848963329 |
| 28 | 24650364462 |
| 29 | 68810859415 |
| 30 | 192439812663 |
| 31 | 539072534278 |
| 32 | 1512285566266 |
[1,1,1,2,5,12,28,65,155,387,1002,2641,7016,18743, 50321,135608,366399,992221,2693705,7333666, 20026582,54858122,150739957,415479332,1148563576, 3183963911,8848963329,24650364462,68810859415, 192439812663,539072534278,1512285566266] |