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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 8 |
| 4 | 8 |
| 5 | 42 |
| 6 | 42 |
| 7 | 208 |
| 8 | 208 |
| 9 | 1042 |
| 10 | 1042 |
| 11 | 5208 |
| 12 | 5208 |
| 13 | 26042 |
| 14 | 26042 |
| 15 | 130208 |
| 16 | 130208 |
| 17 | 651042 |
| 18 | 651042 |
| 19 | 3255208 |
| 20 | 3255208 |
| 21 | 16276042 |
| 22 | 16276042 |
| 23 | 81380208 |
| 24 | 81380208 |
| 25 | 406901042 |
| 26 | 406901042 |
| 27 | 2034505208 |
| 28 | 2034505208 |
| 29 | 10172526042 |
| 30 | 10172526042 |
[2,2,8,8,42,42,208,208,1042,1042,5208,5208,26042, 26042,130208,130208,651042,651042,3255208,3255208, 16276042,16276042,81380208,81380208,406901042, 406901042,2034505208,2034505208,10172526042, 10172526042] |