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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -2 |
| 3 | 3 |
| 4 | 1 |
| 5 | 10 |
| 6 | -176 |
| 7 | 735 |
| 8 | -1707 |
| 9 | 18828 |
| 10 | -251646 |
| 11 | 1819895 |
| 12 | -10653939 |
| 13 | 114938382 |
| 14 | -1464499076 |
| 15 | 11843786955 |
| 16 | -40962861815 |
| 17 | -513203638440 |
| 18 | 26152049892934 |
| 19 | -897502828846005 |
| 20 | 24985080257574265 |
| 21 | -628449474239226990 |
[1,0,-2,3,1,10,-176,735,-1707,18828,-251646, 1819895,-10653939,114938382,-1464499076, 11843786955,-40962861815,-513203638440, 26152049892934,-897502828846005,24985080257574265, -628449474239226990] |