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| n | a(n) |
|---|---|
| 7 | 1 |
| 8 | 2 |
| 9 | 7 |
| 10 | 22 |
| 11 | 73 |
| 12 | 240 |
| 13 | 818 |
| 14 | 2824 |
| 15 | 9995 |
| 16 | 36210 |
| 17 | 134397 |
| 18 | 511802 |
| 19 | 1999360 |
| 20 | 8023808 |
| 21 | 33066865 |
| 22 | 140066840 |
| 23 | 609466485 |
| 24 | 2725084766 |
| 25 | 12510393090 |
| 26 | 58957378290 |
| 27 | 284932585092 |
| 28 | 1411369884766 |
| 29 | 7157365741706 |
| 30 | 37132616218394 |
| 31 | 196866561660145 |
| 32 | 1065754768886044 |
[1,2,7,22,73,240,818,2824,9995,36210,134397, 511802,1999360,8023808,33066865,140066840, 609466485,2725084766,12510393090,58957378290, 284932585092,1411369884766,7157365741706, 37132616218394,196866561660145,1065754768886044] |