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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 10 |
| 4 | 115 |
| 5 | 2126 |
| 6 | 54086 |
| 7 | 1753074 |
| 8 | 69159399 |
| 9 | 3220837534 |
| 10 | 173103073384 |
| 11 | 10551652603526 |
| 12 | 719578430425845 |
| 13 | 54297978110913252 |
| 14 | 4492502634538340722 |
| 15 | 404469190271900056316 |
| 16 | 39370123445405248353743 |
| 17 | 4120204305690280446004838 |
| 18 | 461365717080848755611811094 |
[1,1,10,115,2126,54086,1753074,69159399, 3220837534,173103073384,10551652603526, 719578430425845,54297978110913252, 4492502634538340722,404469190271900056316, 39370123445405248353743,4120204305690280446004838, 461365717080848755611811094] |