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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 18 |
| 3 | 249 |
| 4 | 3132 |
| 5 | 37701 |
| 6 | 443718 |
| 7 | 5159349 |
| 8 | 59589432 |
| 9 | 685658601 |
| 10 | 7872647418 |
| 11 | 90283258449 |
| 12 | 1034650095732 |
| 13 | 11852457339501 |
| 14 | 135745474931118 |
| 15 | 1554484248297549 |
| 16 | 17799805849522032 |
| 17 | 203810186669080401 |
[1,18,249,3132,37701,443718,5159349,59589432, 685658601,7872647418,90283258449,1034650095732, 11852457339501,135745474931118,1554484248297549, 17799805849522032,203810186669080401] |