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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 4 |
| 4 | 6 |
| 5 | 8 |
| 6 | 23 |
| 7 | 42 |
| 8 | 83 |
| 9 | 166 |
| 10 | 324 |
| 11 | 622 |
| 12 | 1236 |
| 13 | 2366 |
| 14 | 4595 |
| 15 | 8900 |
| 16 | 17225 |
| 17 | 33212 |
| 18 | 64376 |
| 19 | 124360 |
| 20 | 240819 |
| 21 | 466284 |
| 22 | 904149 |
| 23 | 1753782 |
| 24 | 3407225 |
| 25 | 6623274 |
| 26 | 12892131 |
| 27 | 25116456 |
| 28 | 48987833 |
| 29 | 95633480 |
| 30 | 186891367 |
| 31 | 365549578 |
| 32 | 715661254 |
| 33 | 1402246154 |
| 34 | 2749778317 |
| 35 | 5396266284 |
[1,0,0,4,6,8,23,42,83,166,324,622,1236,2366,4595, 8900,17225,33212,64376,124360,240819,466284, 904149,1753782,3407225,6623274,12892131,25116456, 48987833,95633480,186891367,365549578,715661254, 1402246154,2749778317,5396266284] |