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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 10 |
| 5 | 20 |
| 6 | 40 |
| 7 | 80 |
| 8 | 159 |
| 9 | 317 |
| 10 | 633 |
| 11 | 1266 |
| 12 | 2532 |
| 13 | 5063 |
| 14 | 10126 |
| 15 | 20252 |
| 16 | 40504 |
| 17 | 81007 |
| 18 | 162014 |
| 19 | 324028 |
| 20 | 648056 |
| 21 | 1296112 |
| 22 | 2592223 |
| 23 | 5184445 |
| 24 | 10368890 |
| 25 | 20737780 |
| 26 | 41475559 |
| 27 | 82951118 |
| 28 | 165902236 |
| 29 | 331804472 |
| 30 | 663608943 |
| 31 | 1327217885 |
| 32 | 2654435770 |
| 33 | 5308871539 |
[1,2,3,5,10,20,40,80,159,317,633,1266,2532,5063, 10126,20252,40504,81007,162014,324028,648056, 1296112,2592223,5184445,10368890,20737780, 41475559,82951118,165902236,331804472,663608943, 1327217885,2654435770,5308871539] |