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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 20 |
| 5 | 16 |
| 6 | 48 |
| 7 | 55 |
| 8 | 128 |
| 9 | 320 |
| 10 | 1206 |
| 11 | 768 |
| 12 | 406446336 |
| 13 | 43545600 |
| 14 | 141312 |
| 15 | 2267136 |
| 16 | 389112 |
| 17 | 1624232 |
| 18 | 138739712 |
| 19 | 122605392 |
| 20 | 2262695936 |
| 21 | 20313407488 |
| 22 | 17060393728 |
| 23 | 189261676544 |
| 24 | 374345132371011500507136 |
| 25 | 669835780976 |
| 26 | -7000008163328 |
| 27 | 22712032822272 |
| 28 | 2244036651776 |
| 29 | 4363027965018112 |
| 30 | 30229121955004416 |
| 31 | -46693326700068864 |
| 32 | -23328907207088128 |
| 33 | 3173005987716005888 |
| 34 | 136427303851761536 |
[1,1,2,2,20,16,48,55,128,320,1206,768,406446336, 43545600,141312,2267136,389112,1624232,138739712, 122605392,2262695936,20313407488,17060393728, 189261676544,374345132371011500507136, 669835780976,-7000008163328,22712032822272, 2244036651776,4363027965018112,30229121955004416, -46693326700068864,-23328907207088128, 3173005987716005888,136427303851761536] |