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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 0 |
| 5 | 44 |
| 6 | -245 |
| 7 | 1917 |
| 8 | -17976 |
| 9 | 191760 |
| 10 | -2268017 |
| 11 | 29862645 |
| 12 | -432485152 |
| 13 | 6819543964 |
| 14 | -116400819509 |
| 15 | 2138673633397 |
| 16 | -42078450265744 |
| 17 | 882702459984256 |
| 18 | -19667723002057473 |
| 19 | 463866294631620941 |
| 20 | -11545312970532620104 |
| 21 | 302416006623761207804 |
| 22 | -8316019118849688156693 |
[0,1,1,5,0,44,-245,1917,-17976,191760,-2268017, 29862645,-432485152,6819543964,-116400819509, 2138673633397,-42078450265744,882702459984256, -19667723002057473,463866294631620941, -11545312970532620104,302416006623761207804, -8316019118849688156693] |