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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 15 |
| 6 | 30 |
| 7 | 57 |
| 8 | 108 |
| 9 | 206 |
| 10 | 393 |
| 11 | 752 |
| 12 | 1439 |
| 13 | 2772 |
| 14 | 5334 |
| 15 | 10327 |
| 16 | 19967 |
| 17 | 38808 |
| 18 | 75319 |
| 19 | 146844 |
| 20 | 285862 |
| 21 | 558723 |
| 22 | 1090370 |
| 23 | 2135551 |
| 24 | 4176224 |
| 25 | 8193490 |
| 26 | 16050930 |
| 27 | 31537017 |
| 28 | 61872863 |
| 29 | 121721157 |
| 30 | 239115024 |
| 31 | 470918888 |
| 32 | 926141652 |
| 33 | 1825708221 |
[1,2,4,8,15,30,57,108,206,393,752,1439,2772,5334, 10327,19967,38808,75319,146844,285862,558723, 1090370,2135551,4176224,8193490,16050930,31537017, 61872863,121721157,239115024,470918888,926141652, 1825708221] |