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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 7 |
| 2 | 77 |
| 3 | 623 |
| 4 | 5355 |
| 5 | 40299 |
| 6 | 317905 |
| 7 | 2323483 |
| 8 | 17353028 |
| 9 | 124991685 |
| 10 | 907465307 |
| 11 | 6458846989 |
| 12 | 46199021001 |
| 13 | 326573565143 |
| 14 | 2314422214435 |
| 15 | 16296707707077 |
| 16 | 114891467946017 |
| 17 | 806991845455033 |
| 18 | 5672334432498356 |
| 19 | 39785054428093380 |
| 20 | 279156880971492454 |
| 21 | 1956352659297436368 |
[1,7,77,623,5355,40299,317905,2323483,17353028, 124991685,907465307,6458846989,46199021001, 326573565143,2314422214435,16296707707077, 114891467946017,806991845455033,5672334432498356, 39785054428093380,279156880971492454, 1956352659297436368] |