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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 6 |
| 7 | 12 |
| 8 | 19 |
| 9 | 62 |
| 10 | 156 |
| 11 | 318 |
| 12 | 852 |
| 13 | 2254 |
| 14 | 5262 |
| 15 | 13441 |
| 16 | 35543 |
| 17 | 88772 |
| 18 | 226880 |
| 19 | 596937 |
| 20 | 1539188 |
| 21 | 3980364 |
| 22 | 10468270 |
| 23 | 27410289 |
| 24 | 71702956 |
| 25 | 189169352 |
| 26 | 499529048 |
| 27 | 1318355542 |
| 28 | 3493861461 |
| 29 | 9278408639 |
| 30 | 24647900618 |
| 31 | 65620808508 |
| 32 | 175037591303 |
| 33 | 467277998136 |
[1,0,0,1,1,1,6,12,19,62,156,318,852,2254,5262, 13441,35543,88772,226880,596937,1539188,3980364, 10468270,27410289,71702956,189169352,499529048, 1318355542,3493861461,9278408639,24647900618, 65620808508,175037591303,467277998136] |