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| n | a(n) |
|---|---|
| 1 | -3 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | -6 |
| 8 | 21 |
| 9 | -56 |
| 10 | 126 |
| 11 | -252 |
| 12 | 463 |
| 13 | -804 |
| 14 | 1365 |
| 15 | -2366 |
| 16 | 4368 |
| 17 | -8736 |
| 18 | 18565 |
| 19 | -40410 |
| 20 | 87381 |
| 21 | -184604 |
| 22 | 379050 |
| 23 | -758100 |
| 24 | 1486675 |
| 25 | -2884776 |
| 26 | 5592405 |
| 27 | -10919090 |
| 28 | 21572460 |
| 29 | -43144920 |
| 30 | 87087001 |
| 31 | -176565486 |
| 32 | 357913941 |
| 33 | -723002336 |
| 34 | 1453179126 |
| 35 | -2906358251 |
[-3,0,0,0,0,1,-6,21,-56,126,-252,463,-804,1365, -2366,4368,-8736,18565,-40410,87381,-184604, 379050,-758100,1486675,-2884776,5592405,-10919090, 21572460,-43144920,87087001,-176565486,357913941, -723002336,1453179126,-2906358251] |