| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 18 |
| 3 | 1498 |
| 4 | 1283090 |
| 5 | 10377556482 |
| 6 | 775351592888722 |
| 7 | 532444511048570910746 |
| 8 | 3349121447720205394546014978 |
| 9 | 192371436319107536207473420480152034 |
| 10 | 100642626897912335112447860229547933463000450 |
[1,2,18,1498,1283090,10377556482,775351592888722, 532444511048570910746, 3349121447720205394546014978, 192371436319107536207473420480152034, 100642626897912335112447860229547933463000450] |