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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 1 |
| 5 | 20 |
| 6 | 4 |
| 7 | 102 |
| 8 | 18 |
| 9 | 626 |
| 10 | 92 |
| 11 | 2 |
| 12 | 4458 |
| 13 | 564 |
| 14 | 18 |
| 15 | 36144 |
| 16 | 4032 |
| 17 | 144 |
| 18 | 328794 |
| 19 | 32898 |
| 20 | 1182 |
| 21 | 6 |
| 22 | 3316944 |
| 23 | 301248 |
| 24 | 10512 |
| 25 | 96 |
| 26 | 36755520 |
| 27 | 3057840 |
| 28 | 102240 |
| 29 | 1200 |
| 30 | 443828184 |
| 31 | 34073184 |
| 32 | 1085904 |
| 33 | 14304 |
| 34 | 24 |
| 35 | 5800823880 |
| 36 | 413484240 |
| 37 | 12538080 |
| 38 | 174000 |
| 39 | 600 |
| 40 | 81591320880 |
[1,1,2,5,1,20,4,102,18,626,92,2,4458,564,18,36144, 4032,144,328794,32898,1182,6,3316944,301248,10512, 96,36755520,3057840,102240,1200,443828184, 34073184,1085904,14304,24,5800823880,413484240, 12538080,174000,600,81591320880] |