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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 33 |
| 4 | 108 |
| 5 | 352 |
| 6 | 1144 |
| 7 | 3714 |
| 8 | 12050 |
| 9 | 39084 |
| 10 | 126752 |
| 11 | 411041 |
| 12 | 1332923 |
| 13 | 4322363 |
| 14 | 14016392 |
| 15 | 45451793 |
| 16 | 147389276 |
| 17 | 477948252 |
| 18 | 1549872500 |
| 19 | 5025868667 |
| 20 | 16297700769 |
| 21 | 52849583211 |
| 22 | 171378684824 |
| 23 | 555740504324 |
| 24 | 1802134907175 |
| 25 | 5843896942499 |
| 26 | 18950374573538 |
[1,3,10,33,108,352,1144,3714,12050,39084,126752, 411041,1332923,4322363,14016392,45451793, 147389276,477948252,1549872500,5025868667, 16297700769,52849583211,171378684824,555740504324, 1802134907175,5843896942499,18950374573538] |