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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 0 |
| 6 | -38 |
| 7 | 0 |
| 8 | 947 |
| 9 | 0 |
| 10 | -37394 |
| 11 | 0 |
| 12 | 2120190 |
| 13 | 0 |
| 14 | -162980012 |
| 15 | 0 |
| 16 | 16330173251 |
| 17 | 0 |
| 18 | -2070201641498 |
| 19 | 0 |
| 20 | 324240251016266 |
| 21 | 0 |
| 22 | -61525045423103316 |
| 23 | 0 |
| 24 | 13913915097436287598 |
| 25 | 0 |
| 26 | -3698477457114061621492 |
| 27 | 0 |
[1,1,-1,0,3,0,-38,0,947,0,-37394,0,2120190,0, -162980012,0,16330173251,0,-2070201641498,0, 324240251016266,0,-61525045423103316,0, 13913915097436287598,0,-3698477457114061621492,0] |