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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 3 |
| 6 | 9 |
| 7 | 24 |
| 8 | 61 |
| 9 | 141 |
| 10 | 322 |
| 11 | 713 |
| 12 | 1543 |
| 13 | 3289 |
| 14 | 6907 |
| 15 | 14353 |
| 16 | 29604 |
| 17 | 60640 |
| 18 | 123522 |
| 19 | 250645 |
| 20 | 506808 |
| 21 | 1022197 |
| 22 | 2057594 |
| 23 | 4135358 |
| 24 | 8301139 |
| 25 | 16648165 |
| 26 | 33364948 |
| 27 | 66831721 |
| 28 | 133814251 |
| 29 | 267850803 |
| 30 | 536026676 |
| 31 | 1072528081 |
| 32 | 2145745276 |
| 33 | 4292485526 |
| 34 | 8586405894 |
| 35 | 17174865820 |
[0,0,0,0,1,3,9,24,61,141,322,713,1543,3289,6907, 14353,29604,60640,123522,250645,506808,1022197, 2057594,4135358,8301139,16648165,33364948, 66831721,133814251,267850803,536026676,1072528081, 2145745276,4292485526,8586405894,17174865820] |