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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 12 |
| 4 | 98 |
| 5 | 684 |
| 6 | 4395 |
| 7 | 26856 |
| 8 | 158692 |
| 9 | 915528 |
| 10 | 5187989 |
| 11 | 28991700 |
| 12 | 160217286 |
| 13 | 877380372 |
| 14 | 4768371583 |
| 15 | 25749206544 |
| 16 | 138282775880 |
| 17 | 739097595216 |
| 18 | 3933906555177 |
| 19 | 20861625671388 |
| 20 | 110268592834474 |
| 21 | 581145286560060 |
| 22 | 3054738044738771 |
| 23 | 16018748283386232 |
| 24 | 83819031715393068 |
[0,1,12,98,684,4395,26856,158692,915528,5187989, 28991700,160217286,877380372,4768371583, 25749206544,138282775880,739097595216, 3933906555177,20861625671388,110268592834474, 581145286560060,3054738044738771, 16018748283386232,83819031715393068] |