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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 21 |
| 4 | 82 |
| 5 | 315 |
| 6 | 1286 |
| 7 | 5353 |
| 8 | 22542 |
| 9 | 96551 |
| 10 | 419059 |
| 11 | 1827498 |
| 12 | 8053542 |
| 13 | 35743165 |
| 14 | 159226263 |
| 15 | 713724911 |
| 16 | 3214402656 |
| 17 | 14516617933 |
| 18 | 65831412369 |
| 19 | 299530825366 |
| 20 | 1365770211716 |
| 21 | 6245955123898 |
| 22 | 28634148921023 |
| 23 | 131495552528622 |
| 24 | 605197211651987 |
| 25 | 2790622072161137 |
| 26 | 12885766896479974 |
| 27 | 59602184029396974 |
[1,2,6,21,82,315,1286,5353,22542,96551,419059, 1827498,8053542,35743165,159226263,713724911, 3214402656,14516617933,65831412369,299530825366, 1365770211716,6245955123898,28634148921023, 131495552528622,605197211651987,2790622072161137, 12885766896479974,59602184029396974] |