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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 0 |
| 5 | 3 |
| 6 | 0 |
| 7 | 3 |
| 8 | 27 |
| 9 | 24 |
| 10 | 0 |
| 11 | 6 |
| 12 | 254 |
| 13 | 734 |
| 14 | 232 |
| 15 | 0 |
| 16 | 24 |
| 17 | 2301 |
| 18 | 19986 |
| 19 | 20448 |
| 20 | 2232 |
| 21 | 0 |
| 22 | 72 |
| 23 | 19053 |
| 24 | 498424 |
| 25 | 1546164 |
| 26 | 549608 |
| 27 | 20880 |
| 28 | 0 |
| 29 | 232 |
| 30 | 149696 |
| 31 | 11256083 |
| 32 | 104452983 |
| 33 | 113887852 |
| 34 | 14309072 |
| 35 | 190656 |
| 36 | 0 |
| 37 | 720 |
| 38 | 1124969 |
| 39 | 239891281 |
| 40 | 6415919752 |
[0,1,0,0,3,0,3,27,24,0,6,254,734,232,0,24,2301, 19986,20448,2232,0,72,19053,498424,1546164,549608, 20880,0,232,149696,11256083,104452983,113887852, 14309072,190656,0,720,1124969,239891281, 6415919752] |