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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 6 |
| 4 | 33 |
| 5 | 185 |
| 6 | 1050 |
| 7 | 6027 |
| 8 | 35014 |
| 9 | 205326 |
| 10 | 1209375 |
| 11 | 7119860 |
| 12 | 41744703 |
| 13 | 243218703 |
| 14 | 1406685280 |
| 15 | 8073640785 |
| 16 | 45991600860 |
| 17 | 260131208396 |
| 18 | 1461591509805 |
| 19 | 8162196518322 |
| 20 | 45327133739245 |
| 21 | 250431036147285 |
| 22 | 1377169337010390 |
| 23 | 7540979990097191 |
| 24 | 41130452834689218 |
| 25 | 223528009015333050 |
| 26 | 1210753768099880875 |
| 27 | 6537995998163877312 |
[0,1,6,33,185,1050,6027,35014,205326,1209375, 7119860,41744703,243218703,1406685280,8073640785, 45991600860,260131208396,1461591509805, 8162196518322,45327133739245,250431036147285, 1377169337010390,7540979990097191, 41130452834689218,223528009015333050, 1210753768099880875,6537995998163877312] |