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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 403 |
| 4 | 11886 |
| 5 | 165152 |
| 6 | 1712052 |
| 7 | 15351085 |
| 8 | 126810474 |
| 9 | 989755263 |
| 10 | 7421134282 |
| 11 | 53972500634 |
| 12 | 383258656118 |
| 13 | 2669593728208 |
| 14 | 18301919622500 |
| 15 | 123810569805676 |
| 16 | 828107771754630 |
| 17 | 5484831030514008 |
| 18 | 36019172324299540 |
| 19 | 234771330638001725 |
[0,0,403,11886,165152,1712052,15351085,126810474, 989755263,7421134282,53972500634,383258656118, 2669593728208,18301919622500,123810569805676, 828107771754630,5484831030514008, 36019172324299540,234771330638001725] |