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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 6 |
| 6 | 2 |
| 7 | 4 |
| 8 | 45 |
| 9 | 36 |
| 10 | 9 |
| 11 | 6 |
| 12 | 408 |
| 13 | 648 |
| 14 | 348 |
| 15 | 76 |
| 16 | 60 |
| 17 | 7195 |
| 18 | 13500 |
| 19 | 11790 |
| 20 | 5280 |
| 21 | 1065 |
| 22 | 120 |
| 23 | 200016 |
| 24 | 369930 |
| 25 | 425280 |
| 26 | 293640 |
| 27 | 118890 |
| 28 | 22566 |
| 29 | 1920 |
| 30 | 13811077 |
| 31 | 14716716 |
| 32 | 18035745 |
| 33 | 16347660 |
| 34 | 9953265 |
| 35 | 3750516 |
| 36 | 674611 |
| 37 | 7560 |
| 38 | 3405271616 |
| 39 | 1024787568 |
| 40 | 971651856 |
| 41 | 999666920 |
| 42 | 794967600 |
| 43 | 445001424 |
| 44 | 157962168 |
| 45 | 27019896 |
[1,1,1,1,6,2,4,45,36,9,6,408,648,348,76,60,7195, 13500,11790,5280,1065,120,200016,369930,425280, 293640,118890,22566,1920,13811077,14716716, 18035745,16347660,9953265,3750516,674611,7560, 3405271616,1024787568,971651856,999666920, 794967600,445001424,157962168,27019896] |