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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 35 |
| 3 | 183 |
| 4 | 948 |
| 5 | 4928 |
| 6 | 25596 |
| 7 | 132993 |
| 8 | 690938 |
| 9 | 3589717 |
| 10 | 18649981 |
| 11 | 96894136 |
| 12 | 503403630 |
| 13 | 2615382795 |
| 14 | 13587956889 |
| 15 | 70594857262 |
| 16 | 366768447408 |
| 17 | 1905508409402 |
| 18 | 9899876400759 |
| 19 | 51433807521668 |
| 20 | 267219149917538 |
| 21 | 1388310092601527 |
[7,35,183,948,4928,25596,132993,690938,3589717, 18649981,96894136,503403630,2615382795, 13587956889,70594857262,366768447408, 1905508409402,9899876400759,51433807521668, 267219149917538,1388310092601527] |