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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 10 |
| 5 | 23 |
| 6 | 48 |
| 7 | 105 |
| 8 | 216 |
| 9 | 467 |
| 10 | 958 |
| 11 | 2021 |
| 12 | 4146 |
| 13 | 8631 |
| 14 | 17604 |
| 15 | 36377 |
| 16 | 73876 |
| 17 | 151379 |
| 18 | 306882 |
| 19 | 625149 |
| 20 | 1263294 |
| 21 | 2563895 |
| 22 | 5169544 |
| 23 | 10454105 |
| 24 | 21046800 |
| 25 | 42451179 |
| 26 | 85334982 |
| 27 | 171799853 |
| 28 | 344952010 |
| 29 | 693368423 |
| 30 | 1391049900 |
| 31 | 2792734257 |
[1,2,5,10,23,48,105,216,467,958,2021,4146,8631, 17604,36377,73876,151379,306882,625149,1263294, 2563895,5169544,10454105,21046800,42451179, 85334982,171799853,344952010,693368423,1391049900, 2792734257] |