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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 4 |
| 7 | 94 |
| 8 | 550 |
| 9 | 2292 |
| 10 | 7552 |
| 11 | 21362 |
| 12 | 52856 |
| 13 | 117694 |
| 14 | 241484 |
| 15 | 463038 |
| 16 | 838816 |
| 17 | 1448002 |
| 18 | 2398292 |
| 19 | 3832374 |
| 20 | 5935120 |
| 21 | 8941514 |
| 22 | 13145292 |
| 23 | 18908302 |
| 24 | 26670584 |
| 25 | 36961170 |
| 26 | 50409604 |
| 27 | 67758182 |
| 28 | 89874912 |
| 29 | 117767194 |
| 30 | 152596220 |
[0,0,0,0,0,0,4,94,550,2292,7552,21362,52856, 117694,241484,463038,838816,1448002,2398292, 3832374,5935120,8941514,13145292,18908302, 26670584,36961170,50409604,67758182,89874912, 117767194,152596220] |