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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 74 |
| 4 | 3078 |
| 5 | 228842 |
| 6 | 25277286 |
| 7 | 3837501194 |
| 8 | 762731347398 |
| 9 | 191798593122602 |
| 10 | 59475206565622566 |
| 11 | 22290155840476400714 |
| 12 | 9933314218291366691718 |
| 13 | 5192540728710234994272362 |
| 14 | 3147427468437058629798524646 |
| 15 | 2190237887318737512524514442634 |
| 16 | 1734606000858253287464231519860038 |
| 17 | 1551466530739217915273113571521758122 |
| 18 | 1556475858078242120174483544923467343526 |
[1,2,6,74,3078,228842,25277286,3837501194, 762731347398,191798593122602,59475206565622566, 22290155840476400714,9933314218291366691718, 5192540728710234994272362, 3147427468437058629798524646, 2190237887318737512524514442634, 1734606000858253287464231519860038, 1551466530739217915273113571521758122, 1556475858078242120174483544923467343526] |