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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 51 |
| 3 | 383 |
| 4 | 2865 |
| 5 | 21449 |
| 6 | 160579 |
| 7 | 1202181 |
| 8 | 9000177 |
| 9 | 67380199 |
| 10 | 504444655 |
| 11 | 3776545835 |
| 12 | 28273267057 |
| 13 | 211668986689 |
| 14 | 1584668649559 |
| 15 | 11863687582089 |
| 16 | 88817989227329 |
| 17 | 664939560807015 |
| 18 | 4978097605819019 |
| 19 | 37268734233506311 |
| 20 | 279013924866426465 |
[7,51,383,2865,21449,160579,1202181,9000177, 67380199,504444655,3776545835,28273267057, 211668986689,1584668649559,11863687582089, 88817989227329,664939560807015,4978097605819019, 37268734233506311,279013924866426465] |