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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 32 |
| 5 | 92 |
| 6 | 264 |
| 7 | 772 |
| 8 | 2272 |
| 9 | 6732 |
| 10 | 20024 |
| 11 | 59732 |
| 12 | 178512 |
| 13 | 534172 |
| 14 | 1599784 |
| 15 | 4793892 |
| 16 | 14370752 |
| 17 | 43090412 |
| 18 | 129227544 |
| 19 | 387595252 |
| 20 | 1162610992 |
| 21 | 3487483452 |
| 22 | 10461751304 |
| 23 | 31383855812 |
| 24 | 94148771232 |
| 25 | 282440721292 |
| 26 | 847310979064 |
[1,2,4,12,32,92,264,772,2272,6732,20024,59732, 178512,534172,1599784,4793892,14370752,43090412, 129227544,387595252,1162610992,3487483452, 10461751304,31383855812,94148771232,282440721292, 847310979064] |