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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 8 |
| 4 | 0 |
| 5 | 86 |
| 6 | 0 |
| 7 | 948 |
| 8 | 0 |
| 9 | 10444 |
| 10 | 0 |
| 11 | 115056 |
| 12 | 0 |
| 13 | 1267512 |
| 14 | 0 |
| 15 | 13963520 |
| 16 | 0 |
| 17 | 153828832 |
| 18 | 0 |
| 19 | 1694652176 |
| 20 | 0 |
| 21 | 18669100976 |
| 22 | 0 |
| 23 | 205667768400 |
| 24 | 0 |
| 25 | 2265734756752 |
| 26 | 0 |
| 27 | 24960420526224 |
| 28 | 0 |
| 29 | 274975961325264 |
| 30 | 0 |
| 31 | 3029267044091408 |
| 32 | 0 |
| 33 | 33371858326057936 |
| 34 | 0 |
| 35 | 367640393509287824 |
| 36 | 0 |
| 37 | 4050102862690348880 |
| 38 | 0 |
| 39 | 44617875206245953552 |
| 40 | 0 |
| 41 | 491531908055724064720 |
| 42 | 0 |
| 43 | 5414951194338345409680 |
| 44 | 0 |
| 45 | 59653698888134291413584 |
| 46 | 0 |
| 47 | 657173751585588653678864 |
| 48 | 0 |
| 49 | 7239741169830151881286864 |
[1,0,8,0,86,0,948,0,10444,0,115056,0,1267512,0, 13963520,0,153828832,0,1694652176,0,18669100976,0, 205667768400,0,2265734756752,0,24960420526224,0, 274975961325264,0,3029267044091408,0, 33371858326057936,0,367640393509287824,0, 4050102862690348880,0,44617875206245953552,0, 491531908055724064720,0,5414951194338345409680,0, 59653698888134291413584,0, 657173751585588653678864,0, 7239741169830151881286864] |