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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 3 |
| 3 | 12 |
| 4 | 48 |
| 5 | 192 |
| 6 | 769 |
| 7 | 3084 |
| 8 | 12381 |
| 9 | 49744 |
| 10 | 199977 |
| 11 | 804276 |
| 12 | 3235668 |
| 13 | 13020192 |
| 14 | 52400538 |
| 15 | 210909656 |
| 16 | 848950359 |
| 17 | 3417275616 |
| 18 | 13755595689 |
| 19 | 55369756356 |
| 20 | 222871001064 |
| 21 | 897051906816 |
| 22 | 3610447601694 |
| 23 | 14530522785576 |
| 24 | 58475788263354 |
| 25 | 235311984533472 |
| 26 | 946856171141034 |
[1,0,3,12,48,192,769,3084,12381,49744,199977, 804276,3235668,13020192,52400538,210909656, 848950359,3417275616,13755595689,55369756356, 222871001064,897051906816,3610447601694, 14530522785576,58475788263354,235311984533472, 946856171141034] |