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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 51 |
| 4 | 228 |
| 5 | 1046 |
| 6 | 4890 |
| 7 | 23163 |
| 8 | 110778 |
| 9 | 533734 |
| 10 | 2586338 |
| 11 | 12590026 |
| 12 | 61513848 |
| 13 | 301461872 |
| 14 | 1481094428 |
| 15 | 7292017771 |
| 16 | 35965507614 |
| 17 | 177657952426 |
| 18 | 878718765970 |
| 19 | 4351160454886 |
| 20 | 21566829418832 |
| 21 | 106989157869960 |
| 22 | 531153575115364 |
| 23 | 2638691991990022 |
| 24 | 13116334236443300 |
| 25 | 65232346007880844 |
| 26 | 324575450192664484 |
[1,3,12,51,228,1046,4890,23163,110778,533734, 2586338,12590026,61513848,301461872,1481094428, 7292017771,35965507614,177657952426,878718765970, 4351160454886,21566829418832,106989157869960, 531153575115364,2638691991990022, 13116334236443300,65232346007880844, 324575450192664484] |