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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 1 |
| 5 | 4 |
| 6 | 0 |
| 7 | 10 |
| 8 | 32 |
| 9 | 42 |
| 10 | 84 |
| 11 | 258 |
| 12 | 581 |
| 13 | 1186 |
| 14 | 3035 |
| 15 | 7988 |
| 16 | 18756 |
| 17 | 47742 |
| 18 | 127617 |
| 19 | 326076 |
| 20 | 846845 |
| 21 | 2256500 |
| 22 | 5951285 |
| 23 | 15714222 |
| 24 | 41838100 |
| 25 | 111313502 |
| 26 | 295853946 |
| 27 | 788065292 |
| 28 | 2101159887 |
| 29 | 5601851162 |
| 30 | 14949652726 |
[0,1,4,0,10,32,42,84,258,581,1186,3035,7988,18756, 47742,127617,326076,846845,2256500,5951285, 15714222,41838100,111313502,295853946,788065292, 2101159887,5601851162,14949652726] |