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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 11 |
| 5 | 30 |
| 6 | 52 |
| 7 | 112 |
| 8 | 265 |
| 9 | 743 |
| 10 | 1224 |
| 11 | 2456 |
| 12 | 4953 |
| 13 | 10119 |
| 14 | 21197 |
| 15 | 46123 |
| 16 | 108490 |
| 17 | 304273 |
| 18 | 500059 |
| 19 | 1000126 |
| 20 | 2000293 |
| 21 | 4000799 |
| 22 | 8002557 |
| 23 | 16008843 |
| 24 | 32033930 |
| 25 | 64155153 |
| 26 | 128701875 |
| 27 | 258903984 |
| 28 | 523810232 |
| 29 | 1071651837 |
| 30 | 2239971619 |
[1,3,4,11,30,52,112,265,743,1224,2456,4953,10119, 21197,46123,108490,304273,500059,1000126,2000293, 4000799,8002557,16008843,32033930,64155153, 128701875,258903984,523810232,1071651837, 2239971619] |