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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 31 |
| 5 | 66 |
| 6 | 185 |
| 7 | 595 |
| 8 | 1760 |
| 9 | 4857 |
| 10 | 13817 |
| 11 | 40388 |
| 12 | 117255 |
| 13 | 336113 |
| 14 | 965514 |
| 15 | 2786619 |
| 16 | 8042407 |
| 17 | 23164130 |
| 18 | 66711425 |
| 19 | 192263523 |
| 20 | 554192616 |
| 21 | 1596983385 |
| 22 | 4601566433 |
| 23 | 13260282324 |
| 24 | 38213747983 |
| 25 | 110121270385 |
| 26 | 317332109746 |
| 27 | 914453225419 |
[1,2,11,31,66,185,595,1760,4857,13817,40388, 117255,336113,965514,2786619,8042407,23164130, 66711425,192263523,554192616,1596983385, 4601566433,13260282324,38213747983,110121270385, 317332109746,914453225419] |