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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 21 |
| 3 | 82 |
| 4 | 105 |
| 5 | 92 |
| 6 | 410 |
| 7 | 945 |
| 8 | 1919 |
| 9 | 4478 |
| 10 | 10274 |
| 11 | 27467 |
| 12 | 73240 |
| 13 | 184074 |
| 14 | 475431 |
| 15 | 1290711 |
| 16 | 3500703 |
| 17 | 9203789 |
| 18 | 24842074 |
| 19 | 67959738 |
| 20 | 185261546 |
| 21 | 500164424 |
| 22 | 1364785665 |
| 23 | 3747581211 |
| 24 | 10238569012 |
| 25 | 27972042011 |
| 26 | 76776169280 |
| 27 | 210809165289 |
[1,21,82,105,92,410,945,1919,4478,10274,27467, 73240,184074,475431,1290711,3500703,9203789, 24842074,67959738,185261546,500164424,1364785665, 3747581211,10238569012,27972042011,76776169280, 210809165289] |