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| n | a(n) |
|---|---|
| 1 | 54 |
| 2 | 81 |
| 3 | 138 |
| 4 | 247 |
| 5 | 462 |
| 6 | 889 |
| 7 | 1740 |
| 8 | 3439 |
| 9 | 6834 |
| 10 | 13621 |
| 11 | 27192 |
| 12 | 54331 |
| 13 | 108606 |
| 14 | 217153 |
| 15 | 434244 |
| 16 | 868423 |
| 17 | 1736778 |
| 18 | 3473485 |
| 19 | 6946896 |
| 20 | 13893715 |
| 21 | 27787350 |
| 22 | 55574617 |
| 23 | 111149148 |
| 24 | 222298207 |
| 25 | 444596322 |
| 26 | 889192549 |
| 27 | 1778385000 |
| 28 | 3556769899 |
| 29 | 7113539694 |
| 30 | 14227079281 |
| 31 | 28454158452 |
[54,81,138,247,462,889,1740,3439,6834,13621,27192, 54331,108606,217153,434244,868423,1736778,3473485, 6946896,13893715,27787350,55574617,111149148, 222298207,444596322,889192549,1778385000, 3556769899,7113539694,14227079281,28454158452] |