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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 115 |
| 3 | 1050 |
| 4 | 9481 |
| 5 | 85392 |
| 6 | 768655 |
| 7 | 6918150 |
| 8 | 62263861 |
| 9 | 560375772 |
| 10 | 5043383995 |
| 11 | 45390460050 |
| 12 | 408514148641 |
| 13 | 3676627354152 |
| 14 | 33089646220135 |
| 15 | 297806816046750 |
| 16 | 2680261344551821 |
| 17 | 24122352101228532 |
| 18 | 217101168911581075 |
[1,12,115,1050,9481,85392,768655,6918150,62263861, 560375772,5043383995,45390460050,408514148641, 3676627354152,33089646220135,297806816046750, 2680261344551821,24122352101228532, 217101168911581075] |