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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 10 |
| 6 | 19 |
| 7 | 35 |
| 8 | 62 |
| 9 | 118 |
| 10 | 219 |
| 11 | 414 |
| 12 | 783 |
| 13 | 1497 |
| 14 | 2860 |
| 15 | 5503 |
| 16 | 10593 |
| 17 | 20471 |
| 18 | 39637 |
| 19 | 76918 |
| 20 | 149501 |
| 21 | 291115 |
| 22 | 567581 |
| 23 | 1108022 |
| 24 | 2165621 |
| 25 | 4237085 |
| 26 | 8297727 |
| 27 | 16264207 |
| 28 | 31904254 |
| 29 | 62630372 |
| 30 | 123031586 |
| 31 | 241837446 |
| 32 | 475647114 |
| 33 | 936020000 |
| 34 | 1842925873 |
[1,2,3,6,10,19,35,62,118,219,414,783,1497,2860, 5503,10593,20471,39637,76918,149501,291115,567581, 1108022,2165621,4237085,8297727,16264207,31904254, 62630372,123031586,241837446,475647114,936020000, 1842925873] |