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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 4 |
| 3 | 0 |
| 4 | 28 |
| 5 | 40 |
| 6 | 36 |
| 7 | 128 |
| 8 | 124 |
| 9 | 680 |
| 10 | 676 |
| 11 | 2688 |
| 12 | 2684 |
| 13 | 10408 |
| 14 | 9380 |
| 15 | 32896 |
| 16 | 31868 |
| 17 | 174760 |
| 18 | 174756 |
| 19 | 699008 |
| 20 | 699004 |
| 21 | 2795688 |
| 22 | 2794660 |
| 23 | 11174016 |
| 24 | 11172988 |
| 25 | 44608168 |
| 26 | 44346020 |
| 27 | 176204416 |
| 28 | 175942268 |
| 29 | 682141864 |
| 30 | 614769828 |
| 31 | 2155905152 |
| 32 | 2088533116 |
| 33 | 11453246120 |
[1,0,4,0,28,40,36,128,124,680,676,2688,2684,10408, 9380,32896,31868,174760,174756,699008,699004, 2795688,2794660,11174016,11172988,44608168, 44346020,176204416,175942268,682141864,614769828, 2155905152,2088533116,11453246120] |