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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 3 |
| 2 | 4 |
| 3 | 14 |
| 4 | 33 |
| 5 | 90 |
| 6 | 232 |
| 7 | 611 |
| 8 | 1596 |
| 9 | 4182 |
| 10 | 10945 |
| 11 | 28658 |
| 12 | 75024 |
| 13 | 196419 |
| 14 | 514228 |
| 15 | 1346270 |
| 16 | 3524577 |
| 17 | 9227466 |
| 18 | 24157816 |
| 19 | 63245987 |
| 20 | 165580140 |
| 21 | 433494438 |
| 22 | 1134903169 |
| 23 | 2971215074 |
| 24 | 7778742048 |
| 25 | 20365011075 |
| 26 | 53316291172 |
| 27 | 139583862446 |
| 28 | 365435296161 |
| 29 | 956722026042 |
[0,3,4,14,33,90,232,611,1596,4182,10945,28658, 75024,196419,514228,1346270,3524577,9227466, 24157816,63245987,165580140,433494438,1134903169, 2971215074,7778742048,20365011075,53316291172, 139583862446,365435296161,956722026042] |