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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 10 |
| 6 | 21 |
| 7 | 39 |
| 8 | 76 |
| 9 | 145 |
| 10 | 294 |
| 11 | 581 |
| 12 | 1169 |
| 13 | 2276 |
| 14 | 4435 |
| 15 | 8494 |
| 16 | 16237 |
| 17 | 30768 |
| 18 | 58221 |
| 19 | 109466 |
| 20 | 205223 |
| 21 | 382658 |
| 22 | 710808 |
| 23 | 1314091 |
| 24 | 2420437 |
| 25 | 4439753 |
| 26 | 8115645 |
| 27 | 14781062 |
| 28 | 26833241 |
| 29 | 48550863 |
| 30 | 87575527 |
| 31 | 157480827 |
| 32 | 282362462 |
| 33 | 504819198 |
| 34 | 900058558 |
| 35 | 1600424247 |
[1,0,0,1,4,10,21,39,76,145,294,581,1169,2276,4435, 8494,16237,30768,58221,109466,205223,382658, 710808,1314091,2420437,4439753,8115645,14781062, 26833241,48550863,87575527,157480827,282362462, 504819198,900058558,1600424247] |