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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -5 |
| 2 | 10 |
| 3 | 50 |
| 4 | -180 |
| 5 | -145 |
| 6 | -700 |
| 7 | 5070 |
| 8 | 10200 |
| 9 | -34475 |
| 10 | 11890 |
| 11 | -344460 |
| 12 | 415800 |
| 13 | 2007660 |
| 14 | -2423460 |
| 15 | 1950250 |
| 16 | -25895760 |
| 17 | 90935120 |
| 18 | 96047350 |
| 19 | -662510900 |
| 20 | -239916420 |
| 21 | -2316837900 |
| 22 | 5593341480 |
| 23 | 24756454910 |
| 24 | -27166986000 |
| 25 | -6558690605 |
| 26 | -190008957720 |
| 27 | 764537004500 |
[1,-5,10,50,-180,-145,-700,5070,10200,-34475, 11890,-344460,415800,2007660,-2423460,1950250, -25895760,90935120,96047350,-662510900,-239916420, -2316837900,5593341480,24756454910,-27166986000, -6558690605,-190008957720,764537004500] |