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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 4 |
| 4 | 87734 |
| 5 | 310732 |
| 6 | 2631724 |
| 7 | 13785346041608 |
| 8 | 303257395102 |
| 9 | 616840823966644 |
| 10 | 6080390575672283210764 |
| 11 | 207461256206578143748856 |
| 12 | 79209152838572743713996404 |
[1,2,2,4,87734,310732,2631724,13785346041608, 303257395102,616840823966644, 6080390575672283210764,207461256206578143748856, 79209152838572743713996404] |