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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 514 |
| 3 | 20199 |
| 4 | 283370 |
| 5 | 2256695 |
| 6 | 12637956 |
| 7 | 55247745 |
| 8 | 202345886 |
| 9 | 644749920 |
| 10 | 1846772550 |
| 11 | 4836548836 |
| 12 | 11795957334 |
| 13 | 27022021703 |
| 14 | 58819382790 |
| 15 | 122237638440 |
| 16 | 244429962966 |
| 17 | 471615005229 |
| 18 | 882955864560 |
| 19 | 1606698758560 |
| 20 | 2853601781340 |
| 21 | 4952029001892 |
| 22 | 8423307325854 |
[0,1,514,20199,283370,2256695,12637956,55247745, 202345886,644749920,1846772550,4836548836, 11795957334,27022021703,58819382790,122237638440, 244429962966,471615005229,882955864560, 1606698758560,2853601781340,4952029001892, 8423307325854] |