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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 0 |
| 5 | 6 |
| 6 | 8 |
| 7 | 2 |
| 8 | 16 |
| 9 | 32 |
| 10 | 52 |
| 11 | 168 |
| 12 | 388 |
| 13 | 910 |
| 14 | 2455 |
| 15 | 6060 |
| 16 | 14635 |
| 17 | 36740 |
| 18 | 92024 |
| 19 | 231576 |
| 20 | 590604 |
| 21 | 1508266 |
| 22 | 3859471 |
| 23 | 9904108 |
| 24 | 25426197 |
| 25 | 65380322 |
| 26 | 168698561 |
| 27 | 436660170 |
| 28 | 1133657509 |
| 29 | 2952149064 |
| 30 | 7708329499 |
| 31 | 20172477506 |
[1,0,6,8,2,16,32,52,168,388,910,2455,6060,14635, 36740,92024,231576,590604,1508266,3859471,9904108, 25426197,65380322,168698561,436660170,1133657509, 2952149064,7708329499,20172477506] |