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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 7 |
| 4 | 13 |
| 5 | 23 |
| 6 | 44 |
| 7 | 81 |
| 8 | 151 |
| 9 | 283 |
| 10 | 529 |
| 11 | 991 |
| 12 | 1855 |
| 13 | 3472 |
| 14 | 6499 |
| 15 | 12167 |
| 16 | 22779 |
| 17 | 42646 |
| 18 | 79840 |
| 19 | 149475 |
| 20 | 279841 |
| 21 | 523911 |
| 22 | 980850 |
| 23 | 1836319 |
| 24 | 3437903 |
| 25 | 6436343 |
| 26 | 12049937 |
| 27 | 22559544 |
| 28 | 42235330 |
| 29 | 79071768 |
| 30 | 148035889 |
[1,2,4,7,13,23,44,81,151,283,529,991,1855,3472, 6499,12167,22779,42646,79840,149475,279841,523911, 980850,1836319,3437903,6436343,12049937,22559544, 42235330,79071768,148035889] |