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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 4 |
| 3 | 11 |
| 4 | 22 |
| 5 | 43 |
| 6 | 85 |
| 7 | 171 |
| 8 | 366 |
| 9 | 774 |
| 10 | 1586 |
| 11 | 3136 |
| 12 | 6123 |
| 13 | 12088 |
| 14 | 24283 |
| 15 | 49040 |
| 16 | 99031 |
| 17 | 200444 |
| 18 | 405931 |
[0,2,4,11,22,43,85,171,366,774,1586,3136,6123, 12088,24283,49040,99031,200444,405931] |