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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 138 |
| 5 | 822 |
| 6 | 2082 |
| 7 | 3918 |
| 8 | 21738 |
| 9 | 39342 |
| 10 | 62130 |
| 11 | 70878 |
| 12 | 106032 |
| 13 | 117372 |
| 14 | 129288 |
| 15 | 135462 |
| 16 | 182712 |
| 17 | 512580 |
| 18 | 524802 |
| 19 | 575130 |
| 20 | 682698 |
| 21 | 769422 |
| 22 | 799482 |
| 23 | 893118 |
| 24 | 1008912 |
| 25 | 1026030 |
| 26 | 1043292 |
| 27 | 1828830 |
| 28 | 2368578 |
| 29 | 2447580 |
| 30 | 3247428 |
| 31 | 3278082 |
| 32 | 3465030 |
| 33 | 4022868 |
| 34 | 4056978 |
[2,4,12,138,822,2082,3918,21738,39342,62130,70878, 106032,117372,129288,135462,182712,512580,524802, 575130,682698,769422,799482,893118,1008912, 1026030,1043292,1828830,2368578,2447580,3247428, 3278082,3465030,4022868,4056978] |