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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 15 |
| 7 | 8456 |
| 8 | 954213 |
| 9 | 66253552 |
| 10 | 3622342095 |
| 11 | 172672602432 |
| 12 | 7557346901841 |
| 13 | 312733696544984 |
| 14 | 12456923582109435 |
| 15 | 483124650731622328 |
| 16 | 18383758048494864909 |
| 17 | 689931203330381971296 |
| 18 | 25630900118611348761735 |
| 19 | 945025181750878420241744 |
| 20 | 34647077709586498046291817 |
[0,0,0,0,0,15,8456,954213,66253552,3622342095, 172672602432,7557346901841,312733696544984, 12456923582109435,483124650731622328, 18383758048494864909,689931203330381971296, 25630900118611348761735,945025181750878420241744, 34647077709586498046291817] |