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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 0 |
| 6 | 4 |
| 7 | 0 |
| 8 | 40 |
| 9 | 0 |
| 10 | 150 |
| 11 | 4 |
| 12 | 610 |
| 13 | 96 |
| 14 | 2798 |
| 15 | 864 |
| 16 | 13218 |
| 17 | 7192 |
| 18 | 64934 |
| 19 | 52332 |
| 20 | 328222 |
| 21 | 339808 |
| 22 | 1727350 |
| 23 | 2177700 |
| 24 | 9454774 |
| 25 | 13785720 |
| 26 | 53012810 |
| 27 | 85897980 |
| 28 | 303909174 |
| 29 | 534416936 |
| 30 | 1779749852 |
| 31 | 3336552436 |
| 32 | 10595394664 |
| 33 | 20885768548 |
| 34 | 63879012118 |
[0,2,0,4,0,40,0,150,4,610,96,2798,864,13218,7192, 64934,52332,328222,339808,1727350,2177700,9454774, 13785720,53012810,85897980,303909174,534416936, 1779749852,3336552436,10595394664,20885768548, 63879012118] |