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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 12 |
| 3 | 72 |
| 4 | 382 |
| 5 | 2104 |
| 6 | 11449 |
| 7 | 62546 |
| 8 | 341249 |
| 9 | 1862631 |
| 10 | 10165343 |
| 11 | 55480071 |
| 12 | 302792766 |
| 13 | 1652555713 |
| 14 | 9019158650 |
| 15 | 49223917246 |
| 16 | 268649627276 |
| 17 | 1466210540982 |
| 18 | 8002145144295 |
| 19 | 43673350799304 |
| 20 | 238356282199103 |
| 21 | 1300878367732021 |
[3,12,72,382,2104,11449,62546,341249,1862631, 10165343,55480071,302792766,1652555713,9019158650, 49223917246,268649627276,1466210540982, 8002145144295,43673350799304,238356282199103, 1300878367732021] |