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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 4 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 12 |
| 13 | 0 |
| 14 | 0 |
| 15 | 0 |
| 16 | 30 |
| 17 | 0 |
| 18 | 0 |
| 19 | 0 |
| 20 | 70 |
| 21 | 0 |
| 22 | 0 |
| 23 | 0 |
| 24 | 165 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 330 |
| 29 | 0 |
| 30 | 0 |
| 31 | 0 |
| 32 | 704 |
| 33 | 0 |
| 34 | 0 |
| 35 | 0 |
| 36 | 1380 |
| 37 | 0 |
| 38 | 0 |
| 39 | 0 |
| 40 | 2688 |
| 41 | 0 |
| 42 | 0 |
| 43 | 0 |
| 44 | 4984 |
| 45 | 0 |
| 46 | 0 |
| 47 | 0 |
| 48 | 9394 |
| 49 | 0 |
| 50 | 0 |
| 51 | 0 |
| 52 | 16665 |
| 53 | 0 |
| 54 | 0 |
| 55 | 0 |
| 56 | 29970 |
| 57 | 0 |
| 58 | 0 |
| 59 | 0 |
| 60 | 52096 |
| 61 | 0 |
| 62 | 0 |
| 63 | 0 |
| 64 | 90090 |
| 65 | 0 |
| 66 | 0 |
| 67 | 0 |
| 68 | 152064 |
| 69 | 0 |
| 70 | 0 |
| 71 | 0 |
[1,0,0,0,1,0,0,0,4,0,0,0,12,0,0,0,30,0,0,0,70,0,0, 0,165,0,0,0,330,0,0,0,704,0,0,0,1380,0,0,0,2688,0, 0,0,4984,0,0,0,9394,0,0,0,16665,0,0,0,29970,0,0,0, 52096,0,0,0,90090,0,0,0,152064,0,0,0] |