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| n | a(n) |
|---|---|
| 50 | 1 |
| 51 | 51 |
| 52 | 1326 |
| 53 | 23426 |
| 54 | 316251 |
| 55 | 3478761 |
| 56 | 32468436 |
| 57 | 264385836 |
| 58 | 1916797311 |
| 59 | 12565671261 |
| 60 | 75394027566 |
| 61 | 418094152866 |
| 62 | 2160153123141 |
| 63 | 10468434365991 |
| 64 | 47855699958816 |
| 65 | 207374699821536 |
| 66 | 855420636763836 |
| 67 | 3371363686069236 |
| 68 | 12736262814039336 |
| 69 | 46252743903616536 |
[1,51,1326,23426,316251,3478761,32468436, 264385836,1916797311,12565671261,75394027566, 418094152866,2160153123141,10468434365991, 47855699958816,207374699821536,855420636763836, 3371363686069236,12736262814039336, 46252743903616536] |