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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 47 |
| 4 | 374 |
| 5 | 3852 |
| 6 | 49398 |
| 7 | 762785 |
| 8 | 13805702 |
| 9 | 286796072 |
| 10 | 6727496456 |
| 11 | 175903776622 |
| 12 | 5073226515772 |
| 13 | 160000741383368 |
| 14 | 5478160073933490 |
| 15 | 202366832844684645 |
| 16 | 8022796547785815878 |
| 17 | 339769654607776375824 |
| 18 | 15309183806159727889536 |
| 19 | 731253261602981693567090 |
| 20 | 36909816019024064633444820 |
[1,2,8,47,374,3852,49398,762785,13805702, 286796072,6727496456,175903776622,5073226515772, 160000741383368,5478160073933490, 202366832844684645,8022796547785815878, 339769654607776375824,15309183806159727889536, 731253261602981693567090, 36909816019024064633444820] |