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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 5 |
| 6 | 12 |
| 7 | 24 |
| 8 | 55 |
| 9 | 119 |
| 10 | 272 |
| 11 | 612 |
| 12 | 1411 |
| 13 | 3247 |
| 14 | 7565 |
| 15 | 17667 |
| 16 | 41561 |
| 17 | 98099 |
| 18 | 232696 |
| 19 | 553784 |
| 20 | 1322813 |
| 21 | 3169065 |
| 22 | 7614583 |
| 23 | 18342921 |
| 24 | 44294991 |
| 25 | 107200829 |
| 26 | 259983346 |
| 27 | 631718606 |
| 28 | 1537737567 |
| 29 | 3749440151 |
| 30 | 9156561590 |
| 31 | 22394270034 |
| 32 | 54845701243 |
| 33 | 134497468359 |
[1,0,1,1,3,5,12,24,55,119,272,612,1411,3247,7565, 17667,41561,98099,232696,553784,1322813,3169065, 7614583,18342921,44294991,107200829,259983346, 631718606,1537737567,3749440151,9156561590, 22394270034,54845701243,134497468359] |