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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 42 |
| 5 | 104 |
| 6 | 140 |
| 7 | 1036 |
| 8 | 1590 |
| 9 | 2730 |
| 10 | 7900 |
| 11 | 10374 |
| 12 | 19180 |
| 13 | 22660 |
| 14 | 23180 |
| 15 | 26418 |
| 16 | 105868 |
| 17 | 114960 |
| 18 | 139060 |
| 19 | 295780 |
| 20 | 403524 |
| 21 | 482250 |
| 22 | 1294144 |
| 23 | 2468944 |
| 24 | 4799058 |
| 25 | 5379282 |
| 26 | 19035500 |
| 27 | 20233936 |
| 28 | 21803860 |
| 29 | 112406992 |
| 30 | 789190976 |
| 31 | 3520928922 |
[1,2,6,42,104,140,1036,1590,2730,7900,10374,19180, 22660,23180,26418,105868,114960,139060,295780, 403524,482250,1294144,2468944,4799058,5379282, 19035500,20233936,21803860,112406992,789190976, 3520928922] |