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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 87 |
| 3 | 740 |
| 4 | 6285 |
| 5 | 53550 |
| 6 | 458115 |
| 7 | 3934600 |
| 8 | 33913881 |
| 9 | 293244050 |
| 10 | 2542684463 |
| 11 | 22101612780 |
| 12 | 192530903461 |
| 13 | 1680415209270 |
| 14 | 14692052109915 |
| 15 | 128653303453200 |
| 16 | 1128147127156785 |
| 17 | 9905115333850650 |
| 18 | 87066787614156807 |
| 19 | 766127762539955700 |
| 20 | 6747880819438628541 |
[1,10,87,740,6285,53550,458115,3934600,33913881, 293244050,2542684463,22101612780,192530903461, 1680415209270,14692052109915,128653303453200, 1128147127156785,9905115333850650, 87066787614156807,766127762539955700, 6747880819438628541] |