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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 5 |
| 5 | 12 |
| 6 | 20 |
| 7 | 41 |
| 8 | 83 |
| 9 | 168 |
| 10 | 254 |
| 11 | 550 |
| 12 | 1121 |
| 13 | 2250 |
| 14 | 4507 |
| 15 | 9015 |
| 16 | 18031 |
| 17 | 36064 |
| 18 | 54098 |
| 19 | 117212 |
| 20 | 238932 |
| 21 | 480121 |
| 22 | 961371 |
| 23 | 1923313 |
| 24 | 3846922 |
| 25 | 7693930 |
| 26 | 15387945 |
| 27 | 30775932 |
| 28 | 61551885 |
| 29 | 123103778 |
| 30 | 246207563 |
| 31 | 492415127 |
| 32 | 984830255 |
| 33 | 1969660512 |
[1,3,4,5,12,20,41,83,168,254,550,1121,2250,4507, 9015,18031,36064,54098,117212,238932,480121, 961371,1923313,3846922,7693930,15387945,30775932, 61551885,123103778,246207563,492415127,984830255, 1969660512] |