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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 43 |
| 4 | 177 |
| 5 | 755 |
| 6 | 3303 |
| 7 | 14727 |
| 8 | 66641 |
| 9 | 305107 |
| 10 | 1410179 |
| 11 | 6568867 |
| 12 | 30799777 |
| 13 | 145214819 |
| 14 | 687917407 |
| 15 | 3272245311 |
| 16 | 15621109601 |
| 17 | 74807650147 |
| 18 | 359245134843 |
| 19 | 1729472608539 |
| 20 | 8344519837009 |
| 21 | 40341962006675 |
| 22 | 195387635818967 |
| 23 | 947870317985783 |
| 24 | 4605206781143857 |
| 25 | 22404849653643955 |
| 26 | 109138628861675123 |
[1,3,11,43,177,755,3303,14727,66641,305107, 1410179,6568867,30799777,145214819,687917407, 3272245311,15621109601,74807650147,359245134843, 1729472608539,8344519837009,40341962006675, 195387635818967,947870317985783,4605206781143857, 22404849653643955,109138628861675123] |