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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 2 |
| 7 | 2 |
| 8 | 13 |
| 9 | 24 |
| 10 | 32 |
| 11 | 118 |
| 12 | 286 |
| 13 | 482 |
| 14 | 1328 |
| 15 | 3540 |
| 16 | 7091 |
| 17 | 17244 |
| 18 | 46138 |
| 19 | 103468 |
| 20 | 243164 |
| 21 | 633618 |
| 22 | 1515992 |
| 23 | 3582432 |
| 24 | 9101608 |
| 25 | 22481022 |
| 26 | 54065300 |
| 27 | 135345444 |
| 28 | 338668916 |
| 29 | 828680300 |
| 30 | 2063798632 |
| 31 | 5185819200 |
| 32 | 12855728210 |
| 33 | 32040478058 |
[1,1,0,0,2,2,2,13,24,32,118,286,482,1328,3540, 7091,17244,46138,103468,243164,633618,1515992, 3582432,9101608,22481022,54065300,135345444, 338668916,828680300,2063798632,5185819200, 12855728210,32040478058] |