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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 5 |
| 4 | 151 |
| 5 | 9944 |
| 6 | 1196991 |
| 7 | 226435150 |
| 8 | 61992679960 |
| 9 | 23198439767669 |
| 10 | 11380100883484302 |
| 11 | 7087878538028540725 |
| 12 | 5465174495550911165171 |
| 13 | 5111311778783673593594175 |
| 14 | 5701234859347275019419890715 |
| 15 | 7477492710871626347942014991975 |
| 16 | 11393306956061559325223329489826611 |
| 17 | 19958666934810234750929365717573438949 |
| 18 | 39835206091758734935374720734513530255512 |
| 19 | 89867076346063005007676287874769844881101800 |
| 20 | 227547795689116560408812799327387232156371842150 |
[1,1,5,151,9944,1196991,226435150,61992679960, 23198439767669,11380100883484302, 7087878538028540725,5465174495550911165171, 5111311778783673593594175, 5701234859347275019419890715, 7477492710871626347942014991975, 11393306956061559325223329489826611, 19958666934810234750929365717573438949, 39835206091758734935374720734513530255512, 89867076346063005007676287874769844881101800, 227547795689116560408812799327387232156371842150] |