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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 47 |
| 3 | 130 |
| 4 | 319 |
| 5 | 755 |
| 6 | 1680 |
| 7 | 3673 |
| 8 | 7751 |
| 9 | 16254 |
| 10 | 33352 |
| 11 | 68448 |
| 12 | 138469 |
| 13 | 281122 |
| 14 | 564810 |
| 15 | 1140621 |
| 16 | 2284335 |
| 17 | 4601127 |
| 18 | 9201288 |
| 19 | 18508319 |
| 20 | 36987885 |
| 21 | 74343834 |
| 22 | 148524185 |
| 23 | 298379462 |
| 24 | 596003105 |
| 25 | 1196923732 |
| 26 | 2390589937 |
| 27 | 4799574872 |
| 28 | 9585538381 |
[16,47,130,319,755,1680,3673,7751,16254,33352, 68448,138469,281122,564810,1140621,2284335, 4601127,9201288,18508319,36987885,74343834, 148524185,298379462,596003105,1196923732, 2390589937,4799574872,9585538381] |