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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 6 |
| 4 | 8 |
| 5 | 20 |
| 6 | 0 |
| 7 | 42 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 110 |
| 12 | 0 |
| 13 | 156 |
| 14 | 0 |
| 15 | 0 |
| 16 | 0 |
| 17 | 272 |
| 18 | 0 |
| 19 | 342 |
| 20 | 0 |
| 21 | 0 |
| 22 | 0 |
| 23 | 506 |
| 24 | 0 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 0 |
| 29 | 812 |
| 30 | 0 |
| 31 | 930 |
| 32 | 0 |
| 33 | 0 |
| 34 | 0 |
| 35 | 0 |
| 36 | 0 |
| 37 | 1332 |
| 38 | 0 |
| 39 | 0 |
| 40 | 0 |
| 41 | 1640 |
| 42 | 0 |
| 43 | 1806 |
| 44 | 0 |
| 45 | 0 |
| 46 | 0 |
| 47 | 2162 |
| 48 | 0 |
| 49 | 0 |
| 50 | 0 |
| 51 | 0 |
| 52 | 0 |
| 53 | 2756 |
| 54 | 0 |
| 55 | 0 |
| 56 | 0 |
| 57 | 0 |
| 58 | 0 |
| 59 | 3422 |
| 60 | 0 |
| 61 | 3660 |
| 62 | 0 |
| 63 | 0 |
| 64 | 0 |
| 65 | 0 |
| 66 | 0 |
| 67 | 4422 |
| 68 | 0 |
| 69 | 0 |
| 70 | 0 |
| 71 | 4970 |
| 72 | 0 |
| 73 | 5256 |
| 74 | 0 |
| 75 | 0 |
| 76 | 0 |
| 77 | 0 |
| 78 | 0 |
| 79 | 6162 |
[0,2,6,8,20,0,42,0,0,0,110,0,156,0,0,0,272,0,342, 0,0,0,506,0,0,0,0,0,812,0,930,0,0,0,0,0,1332,0,0, 0,1640,0,1806,0,0,0,2162,0,0,0,0,0,2756,0,0,0,0,0, 3422,0,3660,0,0,0,0,0,4422,0,0,0,4970,0,5256,0,0, 0,0,0,6162] |