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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 421 |
| 3 | 9091 |
| 4 | 15852 |
| 5 | 92603 |
| 6 | 1551340 |
| 7 | 16130212 |
| 8 | 82774516 |
| 9 | 506265517 |
| 10 | 5660323142 |
| 11 | 51739325680 |
| 12 | 335761691745 |
| 13 | 2418466197168 |
| 14 | 21927716125718 |
| 15 | 184725699865822 |
| 16 | 1350254421406010 |
| 17 | 10284927374810243 |
| 18 | 86141789798720948 |
| 19 | 701278900747323768 |
[0,421,9091,15852,92603,1551340,16130212,82774516, 506265517,5660323142,51739325680,335761691745, 2418466197168,21927716125718,184725699865822, 1350254421406010,10284927374810243, 86141789798720948,701278900747323768] |