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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 12 |
| 5 | 17 |
| 6 | 44 |
| 7 | 74 |
| 8 | 139 |
| 9 | 1123 |
| 10 | 1411 |
| 11 | 2101 |
| 12 | 4070 |
| 13 | 11323 |
| 14 | 11472 |
| 15 | 12870 |
| 16 | 16318 |
| 17 | 16853 |
| 18 | 18729 |
| 19 | 52642 |
| 20 | 132619 |
| 21 | 435644 |
| 22 | 446904 |
| 23 | 168566853 |
| 24 | 350096787 |
| 25 | 521037077 |
| 26 | 708609429 |
| 27 | 1121857192 |
| 28 | 1641773578 |
| 29 | 11947307367 |
| 30 | 21633254881 |
| 31 | 75356090494 |
[1,2,6,12,17,44,74,139,1123,1411,2101,4070,11323, 11472,12870,16318,16853,18729,52642,132619,435644, 446904,168566853,350096787,521037077,708609429, 1121857192,1641773578,11947307367,21633254881, 75356090494] |