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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 7 |
| 3 | 47 |
| 4 | 549 |
| 5 | 7859 |
| 6 | 134743 |
| 7 | 2694537 |
| 8 | 61595593 |
| 9 | 1584039383 |
| 10 | 45262146411 |
| 11 | 1422647401493 |
| 12 | 48780718512397 |
| 13 | 1812012517295811 |
| 14 | 72486789793754911 |
| 15 | 3106846273709042609 |
| 16 | 142039582571511632529 |
| 17 | 6899664100487740573871 |
| 18 | 354870658975988082859219 |
[1,0,7,47,549,7859,134743,2694537,61595593, 1584039383,45262146411,1422647401493, 48780718512397,1812012517295811,72486789793754911, 3106846273709042609,142039582571511632529, 6899664100487740573871,354870658975988082859219] |