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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 4 |
| 6 | 2 |
| 7 | 10 |
| 8 | 6 |
| 9 | 28 |
| 10 | 16 |
| 11 | 76 |
| 12 | 44 |
| 13 | 208 |
| 14 | 120 |
| 15 | 568 |
| 16 | 328 |
| 17 | 1552 |
| 18 | 896 |
| 19 | 4240 |
| 20 | 2448 |
| 21 | 11584 |
| 22 | 6688 |
| 23 | 31648 |
| 24 | 18272 |
| 25 | 86464 |
| 26 | 49920 |
| 27 | 236224 |
| 28 | 136384 |
| 29 | 645376 |
| 30 | 372608 |
| 31 | 1763200 |
| 32 | 1017984 |
| 33 | 4817152 |
| 34 | 2781184 |
| 35 | 13160704 |
| 36 | 7598336 |
| 37 | 35955712 |
| 38 | 20759040 |
| 39 | 98232832 |
[1,0,1,1,4,2,10,6,28,16,76,44,208,120,568,328, 1552,896,4240,2448,11584,6688,31648,18272,86464, 49920,236224,136384,645376,372608,1763200,1017984, 4817152,2781184,13160704,7598336,35955712, 20759040,98232832] |