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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 0 |
| 5 | 4 |
| 6 | 40 |
| 7 | -64 |
| 8 | -1344 |
| 9 | 3984 |
| 10 | 85408 |
| 11 | -356896 |
| 12 | -8462080 |
| 13 | 45908160 |
| 14 | 1209040768 |
| 15 | -8080805888 |
| 16 | -235449260032 |
| 17 | 1871655631104 |
| 18 | 59955521585664 |
| 19 | -552758145525248 |
| 20 | -19339870285225984 |
| 21 | 202927333558572032 |
| 22 | 7707208199780517888 |
| 23 | -90698934927786770432 |
| 24 | -3718489569130941169664 |
| 25 | 48507735629457304555520 |
[0,1,2,2,0,4,40,-64,-1344,3984,85408,-356896, -8462080,45908160,1209040768,-8080805888, -235449260032,1871655631104,59955521585664, -552758145525248,-19339870285225984, 202927333558572032,7707208199780517888, -90698934927786770432,-3718489569130941169664, 48507735629457304555520] |