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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 1 |
| 4 | 16 |
| 5 | 55 |
| 6 | 24 |
| 7 | 135 |
| 8 | 352 |
| 9 | 799 |
| 10 | 0 |
| 11 | 2303 |
| 12 | 8064 |
| 13 | 255 |
| 14 | 31872 |
| 15 | 15231 |
| 16 | 111104 |
| 17 | 11775 |
| 18 | 379904 |
| 19 | 828415 |
| 20 | 217088 |
| 21 | 2797567 |
| 22 | 8216576 |
| 23 | 663551 |
| 24 | 32997376 |
| 25 | 12222463 |
| 26 | 126779392 |
| 27 | 56229887 |
| 28 | 535461888 |
| 29 | 85458943 |
| 30 | 1872920576 |
| 31 | 89620479 |
| 32 | 5346557952 |
| 33 | 16464609279 |
| 34 | 2059141120 |
[1,2,6,1,16,55,24,135,352,799,0,2303,8064,255, 31872,15231,111104,11775,379904,828415,217088, 2797567,8216576,663551,32997376,12222463, 126779392,56229887,535461888,85458943,1872920576, 89620479,5346557952,16464609279,2059141120] |