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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 3 |
| 6 | 2 |
| 7 | 9 |
| 8 | 0 |
| 9 | 28 |
| 10 | 24 |
| 11 | 93 |
| 12 | 20 |
| 13 | 315 |
| 14 | 288 |
| 15 | 1091 |
| 16 | 0 |
| 17 | 3855 |
| 18 | 3626 |
| 19 | 13797 |
| 20 | 3264 |
| 21 | 49929 |
| 22 | 47616 |
| 23 | 182361 |
| 24 | 2720 |
| 25 | 671088 |
| 26 | 645120 |
| 27 | 2485504 |
| 28 | 599040 |
| 29 | 9256395 |
| 30 | 8947294 |
| 31 | 34636833 |
| 32 | 0 |
| 33 | 130150493 |
| 34 | 126320640 |
| 35 | 490853403 |
| 36 | 119302820 |
| 37 | 1857283155 |
| 38 | 1808400384 |
| 39 | 7048151355 |
[1,0,1,0,3,2,9,0,28,24,93,20,315,288,1091,0,3855, 3626,13797,3264,49929,47616,182361,2720,671088, 645120,2485504,599040,9256395,8947294,34636833,0, 130150493,126320640,490853403,119302820, 1857283155,1808400384,7048151355] |