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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | -5 |
| 6 | 9 |
| 7 | 287 |
| 8 | -4455 |
| 9 | 84249 |
| 10 | -284515 |
| 11 | -35428349 |
| 12 | 814639275 |
| 13 | -3434408341 |
| 14 | -1338006522699 |
| 15 | 6133774365735 |
| 16 | 413520124707781 |
| 17 | -45122925184812203 |
| 18 | -231704968682873565 |
| 19 | 102526632234397695073 |
| 20 | -2030875572224787003585 |
| 21 | -76894817276627723872401 |
[0,1,1,0,1,-5,9,287,-4455,84249,-284515,-35428349, 814639275,-3434408341,-1338006522699, 6133774365735,413520124707781,-45122925184812203, -231704968682873565,102526632234397695073, -2030875572224787003585,-76894817276627723872401] |