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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 12 |
| 3 | 98 |
| 4 | 1128 |
| 5 | 16442 |
| 6 | 293356 |
| 7 | 6195114 |
| 8 | 151432112 |
| 9 | 4209004466 |
| 10 | 131188519764 |
| 11 | 4533821784098 |
| 12 | 172125130420744 |
| 13 | 7122734349079338 |
| 14 | 319148172778019708 |
| 15 | 15395906192167996058 |
| 16 | 795673541794111734624 |
| 17 | 43862837291529529270370 |
[1,2,12,98,1128,16442,293356,6195114,151432112, 4209004466,131188519764,4533821784098, 172125130420744,7122734349079338, 319148172778019708,15395906192167996058, 795673541794111734624,43862837291529529270370] |