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| n | a(n) |
|---|---|
| 3 | 3 |
| 4 | 23 |
| 5 | 155 |
| 6 | 1014 |
| 7 | 6580 |
| 8 | 42636 |
| 9 | 276507 |
| 10 | 1796300 |
| 11 | 11692395 |
| 12 | 76257675 |
| 13 | 498286932 |
| 14 | 3261636728 |
| 15 | 21384163320 |
| 16 | 140407901032 |
| 17 | 923165093595 |
| 18 | 6077239852824 |
| 19 | 40052346318985 |
| 20 | 264243349910925 |
| 21 | 1745013401135235 |
| 22 | 11533997779931550 |
| 23 | 76298933599198800 |
| 24 | 505113085597039920 |
| 25 | 3346315941511650900 |
[3,23,155,1014,6580,42636,276507,1796300,11692395, 76257675,498286932,3261636728,21384163320, 140407901032,923165093595,6077239852824, 40052346318985,264243349910925,1745013401135235, 11533997779931550,76298933599198800, 505113085597039920,3346315941511650900] |