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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 8 |
| 3 | 0 |
| 4 | 189 |
| 5 | 0 |
| 6 | 5040 |
| 7 | 0 |
| 8 | 134521 |
| 9 | 0 |
| 10 | 3580920 |
| 11 | 0 |
| 12 | 95235525 |
| 13 | 0 |
| 14 | 2532193248 |
| 15 | 0 |
| 16 | 67323825121 |
| 17 | 0 |
| 18 | 1789924262120 |
| 19 | 0 |
| 20 | 47588184605133 |
| 21 | 0 |
| 22 | 1265212011626640 |
| 23 | 0 |
| 24 | 33637786102201993 |
| 25 | 0 |
| 26 | 894317001840696408 |
| 27 | 0 |
| 28 | 23776918341948436245 |
| 29 | 0 |
[0,8,0,189,0,5040,0,134521,0,3580920,0,95235525,0, 2532193248,0,67323825121,0,1789924262120,0, 47588184605133,0,1265212011626640,0, 33637786102201993,0,894317001840696408,0, 23776918341948436245,0] |