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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 13 |
| 5 | 27 |
| 6 | 55 |
| 7 | 110 |
| 8 | 220 |
| 9 | 440 |
| 10 | 881 |
| 11 | 1762 |
| 12 | 3524 |
| 13 | 7048 |
| 14 | 14097 |
| 15 | 28195 |
| 16 | 56390 |
| 17 | 112781 |
| 18 | 225562 |
| 19 | 451125 |
| 20 | 902250 |
| 21 | 1804500 |
| 22 | 3609000 |
| 23 | 7218000 |
| 24 | 14436001 |
| 25 | 28872002 |
| 26 | 57744005 |
| 27 | 115488011 |
| 28 | 230976023 |
| 29 | 461952047 |
| 30 | 923904094 |
| 31 | 1847808189 |
[1,3,6,13,27,55,110,220,440,881,1762,3524,7048, 14097,28195,56390,112781,225562,451125,902250, 1804500,3609000,7218000,14436001,28872002, 57744005,115488011,230976023,461952047,923904094, 1847808189] |