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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -1 |
| 3 | -4 |
| 4 | -4 |
| 5 | 4 |
| 6 | 17 |
| 7 | 17 |
| 8 | -17 |
| 9 | -72 |
| 10 | -72 |
| 11 | 72 |
| 12 | 305 |
| 13 | 305 |
| 14 | -305 |
| 15 | -1292 |
| 16 | -1292 |
| 17 | 1292 |
| 18 | 5473 |
| 19 | 5473 |
| 20 | -5473 |
| 21 | -23184 |
| 22 | -23184 |
| 23 | 23184 |
| 24 | 98209 |
| 25 | 98209 |
| 26 | -98209 |
| 27 | -416020 |
| 28 | -416020 |
| 29 | 416020 |
| 30 | 1762289 |
| 31 | 1762289 |
| 32 | -1762289 |
| 33 | -7465176 |
| 34 | -7465176 |
| 35 | 7465176 |
| 36 | 31622993 |
| 37 | 31622993 |
[1,1,-1,-4,-4,4,17,17,-17,-72,-72,72,305,305,-305, -1292,-1292,1292,5473,5473,-5473,-23184,-23184, 23184,98209,98209,-98209,-416020,-416020,416020, 1762289,1762289,-1762289,-7465176,-7465176, 7465176,31622993,31622993] |