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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 6 |
| 7 | 21 |
| 8 | 56 |
| 9 | 126 |
| 10 | 253 |
| 11 | 474 |
| 12 | 870 |
| 13 | 1651 |
| 14 | 3367 |
| 15 | 7372 |
| 16 | 16762 |
| 17 | 38183 |
| 18 | 85290 |
| 19 | 185573 |
| 20 | 394555 |
| 21 | 826752 |
| 22 | 1724816 |
| 23 | 3613968 |
| 24 | 7642004 |
| 25 | 16313856 |
| 26 | 35052905 |
| 27 | 75487110 |
| 28 | 162349105 |
| 29 | 348018300 |
| 30 | 743376838 |
| 31 | 1583718457 |
| 32 | 3370144462 |
| 33 | 7173308802 |
| 34 | 15285181447 |
[1,0,0,0,0,1,6,21,56,126,253,474,870,1651,3367, 7372,16762,38183,85290,185573,394555,826752, 1724816,3613968,7642004,16313856,35052905, 75487110,162349105,348018300,743376838,1583718457, 3370144462,7173308802,15285181447] |