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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 0 |
| 8 | -3 |
| 9 | -13 |
| 10 | -39 |
| 11 | -107 |
| 12 | -273 |
| 13 | -675 |
| 14 | -1624 |
| 15 | -3847 |
| 16 | -8995 |
| 17 | -20851 |
| 18 | -47995 |
| 19 | -109915 |
| 20 | -250695 |
| 21 | -570024 |
| 22 | -1292915 |
| 23 | -2926953 |
| 24 | -6616051 |
| 25 | -14936895 |
| 26 | -33690357 |
| 27 | -75931283 |
| 28 | -171029936 |
| 29 | -385046687 |
| 30 | -866536007 |
| 31 | -1949510615 |
| 32 | -4384874471 |
| 33 | -9860587191 |
| 34 | -22170707871 |
| 35 | -49842661456 |
[1,1,1,1,1,1,0,-3,-13,-39,-107,-273,-675,-1624, -3847,-8995,-20851,-47995,-109915,-250695,-570024, -1292915,-2926953,-6616051,-14936895,-33690357, -75931283,-171029936,-385046687,-866536007, -1949510615,-4384874471,-9860587191,-22170707871, -49842661456] |