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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 6 |
| 6 | 77 |
| 7 | 504 |
| 8 | 2304 |
| 9 | 8350 |
| 10 | 25653 |
| 11 | 69576 |
| 12 | 171106 |
| 13 | 388752 |
| 14 | 827190 |
| 15 | 1665456 |
| 16 | 3198312 |
| 17 | 5895396 |
| 18 | 10483934 |
| 19 | 18062160 |
| 20 | 30252180 |
| 21 | 49402850 |
| 22 | 78855339 |
| 23 | 123286440 |
| 24 | 189147400 |
| 25 | 285219090 |
| 26 | 423307755 |
| 27 | 619109400 |
| 28 | 893275110 |
| 29 | 1272714300 |
| 30 | 1792178076 |
[0,0,0,0,6,77,504,2304,8350,25653,69576,171106, 388752,827190,1665456,3198312,5895396,10483934, 18062160,30252180,49402850,78855339,123286440, 189147400,285219090,423307755,619109400,893275110, 1272714300,1792178076] |