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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 57 |
| 3 | 701 |
| 4 | 10147 |
| 5 | 164317 |
| 6 | 2888282 |
| 7 | 54047434 |
| 8 | 1062530119 |
| 9 | 21739192762 |
| 10 | 459685114665 |
| 11 | 9993072855135 |
| 12 | 222421656113435 |
| 13 | 5052215132332492 |
| 14 | 116808526607319823 |
| 15 | 2742986603349411311 |
| 16 | 65306671610636210891 |
| 17 | 1574090246599071243962 |
| 18 | 38361262640988126803839 |
[1,6,57,701,10147,164317,2888282,54047434, 1062530119,21739192762,459685114665,9993072855135, 222421656113435,5052215132332492, 116808526607319823,2742986603349411311, 65306671610636210891,1574090246599071243962, 38361262640988126803839] |