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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | -4 |
| 4 | -11 |
| 5 | -30 |
| 6 | -79 |
| 7 | -208 |
| 8 | -545 |
| 9 | -1428 |
| 10 | -3739 |
| 11 | -9790 |
| 12 | -25631 |
| 13 | -67104 |
| 14 | -175681 |
| 15 | -459940 |
| 16 | -1204139 |
| 17 | -3152478 |
| 18 | -8253295 |
| 19 | -21607408 |
| 20 | -56568929 |
| 21 | -148099380 |
| 22 | -387729211 |
| 23 | -1015088254 |
| 24 | -2657535551 |
| 25 | -6957518400 |
| 26 | -18215019649 |
| 27 | -47687540548 |
| 28 | -124847601995 |
| 29 | -326855265438 |
[1,0,-1,-4,-11,-30,-79,-208,-545,-1428,-3739, -9790,-25631,-67104,-175681,-459940,-1204139, -3152478,-8253295,-21607408,-56568929,-148099380, -387729211,-1015088254,-2657535551,-6957518400, -18215019649,-47687540548,-124847601995, -326855265438] |