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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 12 |
| 5 | 23 |
| 6 | 45 |
| 7 | 87 |
| 8 | 171 |
| 9 | 336 |
| 10 | 666 |
| 11 | 1320 |
| 12 | 2628 |
| 13 | 5233 |
| 14 | 10443 |
| 15 | 20841 |
| 16 | 41637 |
| 17 | 83187 |
| 18 | 166287 |
| 19 | 332403 |
| 20 | 664635 |
| 21 | 1328934 |
| 22 | 2657532 |
| 23 | 5314398 |
| 24 | 10628130 |
| 25 | 21254940 |
| 26 | 42508560 |
| 27 | 85014492 |
| 28 | 170026356 |
| 29 | 340047479 |
| 30 | 680089725 |
| 31 | 1360169007 |
| 32 | 2720327571 |
[1,3,6,12,23,45,87,171,336,666,1320,2628,5233, 10443,20841,41637,83187,166287,332403,664635, 1328934,2657532,5314398,10628130,21254940, 42508560,85014492,170026356,340047479,680089725, 1360169007,2720327571] |