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| n | a(n) |
|---|---|
| 51 | 1 |
| 52 | 52 |
| 53 | 1378 |
| 54 | 24804 |
| 55 | 341055 |
| 56 | 3819816 |
| 57 | 36288252 |
| 58 | 300674088 |
| 59 | 2217471399 |
| 60 | 14783142660 |
| 61 | 90177170226 |
| 62 | 508271323092 |
| 63 | 2668424446233 |
| 64 | 13136858812224 |
| 65 | 60992558771040 |
| 66 | 268367258592576 |
| 67 | 1123787895356412 |
| 68 | 4495151581425648 |
[1,52,1378,24804,341055,3819816,36288252, 300674088,2217471399,14783142660,90177170226, 508271323092,2668424446233,13136858812224, 60992558771040,268367258592576,1123787895356412, 4495151581425648] |