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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 41 |
| 2 | 860 |
| 3 | 12300 |
| 4 | 134889 |
| 5 | 1209377 |
| 6 | 9230207 |
| 7 | 61657399 |
| 8 | 367846424 |
| 9 | 1990342376 |
| 10 | 9885562358 |
| 11 | 45508669878 |
| 12 | 195729780567 |
| 13 | 791712506207 |
| 14 | 3028721321382 |
| 15 | 11010682764150 |
| 16 | 38197208930405 |
| 17 | 126905454993645 |
| 18 | 405078061871575 |
[1,41,860,12300,134889,1209377,9230207,61657399, 367846424,1990342376,9885562358,45508669878, 195729780567,791712506207,3028721321382, 11010682764150,38197208930405,126905454993645, 405078061871575] |