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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 7 |
| 6 | 22 |
| 7 | 61 |
| 8 | 172 |
| 9 | 528 |
| 10 | 1696 |
| 11 | 5461 |
| 12 | 17591 |
| 13 | 57356 |
| 14 | 189786 |
| 15 | 634137 |
| 16 | 2131628 |
| 17 | 7205426 |
| 18 | 24500143 |
| 19 | 83760349 |
| 20 | 287672215 |
| 21 | 991932713 |
| 22 | 3432816902 |
| 23 | 11920342010 |
| 24 | 41521046864 |
| 25 | 145032773711 |
| 26 | 507902711094 |
| 27 | 1782900884412 |
| 28 | 6272354908197 |
| 29 | 22111650029873 |
| 30 | 78097290365451 |
| 31 | 276324399241123 |
| 32 | 979311618314876 |
[1,1,1,2,7,22,61,172,528,1696,5461,17591,57356, 189786,634137,2131628,7205426,24500143,83760349, 287672215,991932713,3432816902,11920342010, 41521046864,145032773711,507902711094, 1782900884412,6272354908197,22111650029873, 78097290365451,276324399241123,979311618314876] |