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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 18 |
| 4 | 144 |
| 5 | 1605 |
| 6 | 1242 |
| 7 | 1799 |
| 8 | 2760 |
| 9 | 3276 |
| 10 | 0 |
| 11 | 858 |
| 12 | 31068 |
| 13 | 32357 |
| 14 | 66178 |
| 15 | 479925 |
| 16 | 192896 |
| 17 | 141457 |
| 18 | 271890 |
| 19 | 220495 |
| 20 | 0 |
| 21 | 298578 |
| 22 | 44066 |
| 23 | 407491 |
| 24 | 663480 |
| 25 | 1632125 |
| 26 | 820820 |
| 27 | 1273968 |
| 28 | 931756 |
| 29 | 1020539 |
| 30 | 0 |
| 31 | 1405416 |
| 32 | 2283104 |
| 33 | 149754 |
| 34 | 2553672 |
[1,6,18,144,1605,1242,1799,2760,3276,0,858,31068, 32357,66178,479925,192896,141457,271890,220495,0, 298578,44066,407491,663480,1632125,820820,1273968, 931756,1020539,0,1405416,2283104,149754,2553672] |