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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 2 |
| 4 | 9 |
| 5 | 24 |
| 6 | 42 |
| 7 | 90 |
| 8 | 213 |
| 9 | 597 |
| 10 | 984 |
| 11 | 1974 |
| 12 | 3981 |
| 13 | 8133 |
| 14 | 17037 |
| 15 | 37071 |
| 16 | 87198 |
| 17 | 244557 |
| 18 | 401919 |
| 19 | 803844 |
| 20 | 1607721 |
| 21 | 3215613 |
| 22 | 6431997 |
| 23 | 12866991 |
| 24 | 25747038 |
| 25 | 51564237 |
| 26 | 103443195 |
| 27 | 208092192 |
| 28 | 421008660 |
| 29 | 861332361 |
| 30 | 1800360879 |
| 31 | 3918287223 |
| 32 | 9215926665 |
| 33 | 25847419116 |
| 34 | 42478911570 |
| 35 | 84957823146 |
[1,3,2,9,24,42,90,213,597,984,1974,3981,8133, 17037,37071,87198,244557,401919,803844,1607721, 3215613,6431997,12866991,25747038,51564237, 103443195,208092192,421008660,861332361, 1800360879,3918287223,9215926665,25847419116, 42478911570,84957823146] |