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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 13 |
| 5 | 116 |
| 6 | 661 |
| 7 | 8632 |
| 8 | 70617 |
| 9 | 1247248 |
| 10 | 13329001 |
| 11 | 285675776 |
| 12 | 3782734693 |
| 13 | 107823153088 |
| 14 | 1685127882621 |
| 15 | 28683829833856 |
| 16 | 574020572798641 |
| 17 | 133507199865641216 |
| 18 | 2477747434090344913 |
| 19 | -832289494713919714304 |
| 20 | -16453576647394853560899 |
| 21 | 11260772482520581109810176 |
| 22 | 246622016098219255086463333 |
| 23 | -219530418791080092679815129088 |
| 24 | -5247252347909156791432867741559 |
| 25 | 6177525915951437030555334153342976 |
| 26 | 160073955175697692672876432040185401 |
[1,1,1,4,13,116,661,8632,70617,1247248,13329001, 285675776,3782734693,107823153088,1685127882621, 28683829833856,574020572798641,133507199865641216, 2477747434090344913,-832289494713919714304, -16453576647394853560899, 11260772482520581109810176, 246622016098219255086463333, -219530418791080092679815129088, -5247252347909156791432867741559, 6177525915951437030555334153342976, 160073955175697692672876432040185401] |