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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 52 |
| 2 | 1053 |
| 3 | 12376 |
| 4 | 100776 |
| 5 | 627912 |
| 6 | 3187041 |
| 7 | 13748020 |
| 8 | 51949755 |
| 9 | 175847880 |
| 10 | 542393670 |
| 11 | 1544927904 |
| 12 | 4107092288 |
| 13 | 10278624864 |
| 14 | 24388573014 |
| 15 | 55188666312 |
| 16 | 119696471453 |
| 17 | 249869263644 |
| 18 | 503865726155 |
| 19 | 984563860280 |
| 20 | 1869304764600 |
| 21 | 3456658569000 |
| 22 | 6238533257775 |
[1,52,1053,12376,100776,627912,3187041,13748020, 51949755,175847880,542393670,1544927904, 4107092288,10278624864,24388573014,55188666312, 119696471453,249869263644,503865726155, 984563860280,1869304764600,3456658569000, 6238533257775] |