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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 46 |
| 4 | 310 |
| 5 | 2411 |
| 6 | 19665 |
| 7 | 166230 |
| 8 | 1440495 |
| 9 | 12712499 |
| 10 | 113765625 |
| 11 | 1029518337 |
| 12 | 9401997000 |
| 13 | 86516427946 |
| 14 | 801235615814 |
[1,7,46,310,2411,19665,166230,1440495,12712499, 113765625,1029518337,9401997000,86516427946, 801235615814] |