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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 12 |
| 5 | 41 |
| 6 | 70 |
| 7 | 239 |
| 8 | 408 |
| 9 | 1393 |
| 10 | 2378 |
| 11 | 8119 |
| 12 | 13860 |
| 13 | 47321 |
| 14 | 80782 |
| 15 | 275807 |
| 16 | 470832 |
| 17 | 1607521 |
| 18 | 2744210 |
| 19 | 9369319 |
| 20 | 15994428 |
| 21 | 54608393 |
| 22 | 93222358 |
| 23 | 318281039 |
| 24 | 543339720 |
| 25 | 1855077841 |
| 26 | 3166815962 |
| 27 | 10812186007 |
| 28 | 18457556052 |
| 29 | 63018038201 |
| 30 | 107578520350 |
[1,2,7,12,41,70,239,408,1393,2378,8119,13860, 47321,80782,275807,470832,1607521,2744210,9369319, 15994428,54608393,93222358,318281039,543339720, 1855077841,3166815962,10812186007,18457556052, 63018038201,107578520350] |