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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 48 |
| 4 | 443 |
| 5 | 4445 |
| 6 | 47107 |
| 7 | 518835 |
| 8 | 5880223 |
| 9 | 68130860 |
| 10 | 803369481 |
| 11 | 9609294542 |
| 12 | 116310009888 |
| 13 | 1421951861817 |
| 14 | 17533301767624 |
| 15 | 217796367181117 |
| 16 | 2722942699583650 |
| 17 | 34236790400004432 |
| 18 | 432649744252128084 |
| 19 | 5492060945760586212 |
| 20 | 69998993052214823013 |
[1,1,6,48,443,4445,47107,518835,5880223,68130860, 803369481,9609294542,116310009888,1421951861817, 17533301767624,217796367181117,2722942699583650, 34236790400004432,432649744252128084, 5492060945760586212,69998993052214823013] |