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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 3 |
| 3 | 9 |
| 4 | 24 |
| 5 | 62 |
| 6 | 134 |
| 7 | 277 |
| 8 | 542 |
| 9 | 1035 |
| 10 | 1930 |
| 11 | 3546 |
| 12 | 6432 |
| 13 | 11555 |
| 14 | 20590 |
| 15 | 36445 |
| 16 | 64140 |
| 17 | 112326 |
| 18 | 195866 |
| 19 | 340241 |
| 20 | 589038 |
| 21 | 1016671 |
| 22 | 1749950 |
| 23 | 3004610 |
| 24 | 5147092 |
| 25 | 8798911 |
| 26 | 15012766 |
| 27 | 25569393 |
| 28 | 43477440 |
| 29 | 73814414 |
| 30 | 125140142 |
| 31 | 211870477 |
| 32 | 358260350 |
[0,3,9,24,62,134,277,542,1035,1930,3546,6432, 11555,20590,36445,64140,112326,195866,340241, 589038,1016671,1749950,3004610,5147092,8798911, 15012766,25569393,43477440,73814414,125140142, 211870477,358260350] |