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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 8 |
| 6 | 18 |
| 7 | 39 |
| 8 | 81 |
| 9 | 164 |
| 10 | 326 |
| 11 | 639 |
| 12 | 1239 |
| 13 | 2382 |
| 14 | 4548 |
| 15 | 8635 |
| 16 | 16319 |
| 17 | 30722 |
| 18 | 57650 |
| 19 | 107885 |
| 20 | 201425 |
| 21 | 375322 |
| 22 | 698162 |
| 23 | 1296801 |
| 24 | 2405707 |
| 25 | 4457984 |
| 26 | 8253228 |
| 27 | 15266969 |
| 28 | 28220967 |
| 29 | 52134000 |
| 30 | 96257558 |
| 31 | 177640983 |
| 32 | 327696621 |
| 33 | 604287700 |
| 34 | 1113981922 |
| 35 | 2053015399 |
[0,0,0,1,3,8,18,39,81,164,326,639,1239,2382,4548, 8635,16319,30722,57650,107885,201425,375322, 698162,1296801,2405707,4457984,8253228,15266969, 28220967,52134000,96257558,177640983,327696621, 604287700,1113981922,2053015399] |