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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 90 |
| 4 | 720 |
| 5 | 5761 |
| 6 | 46091 |
| 7 | 368730 |
| 8 | 2949840 |
| 9 | 23598721 |
| 10 | 188789771 |
| 11 | 1510318170 |
| 12 | 12082545360 |
| 13 | 96660362881 |
| 14 | 773282903051 |
| 15 | 6186263224410 |
| 16 | 49490105795280 |
| 17 | 395920846362241 |
| 18 | 3167366770897931 |
[1,11,90,720,5761,46091,368730,2949840,23598721, 188789771,1510318170,12082545360,96660362881, 773282903051,6186263224410,49490105795280, 395920846362241,3167366770897931] |