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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 9 |
| 6 | 15 |
| 7 | 20 |
| 8 | 0 |
| 9 | 0 |
| 10 | 45 |
| 11 | 54 |
| 12 | 66 |
| 13 | 77 |
| 14 | 0 |
| 15 | 0 |
| 16 | 120 |
| 17 | 135 |
| 18 | 153 |
| 19 | 170 |
| 20 | 0 |
| 21 | 0 |
| 22 | 231 |
| 23 | 252 |
| 24 | 0 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 378 |
| 29 | 405 |
| 30 | 435 |
| 31 | 464 |
| 32 | 0 |
| 33 | 0 |
| 34 | 0 |
| 35 | 0 |
| 36 | 630 |
| 37 | 665 |
| 38 | 0 |
| 39 | 0 |
| 40 | 780 |
| 41 | 819 |
| 42 | 861 |
| 43 | 902 |
| 44 | 0 |
| 45 | 0 |
| 46 | 1035 |
| 47 | 1080 |
| 48 | 0 |
| 49 | 0 |
| 50 | 0 |
| 51 | 0 |
| 52 | 1326 |
| 53 | 1377 |
| 54 | 0 |
| 55 | 0 |
| 56 | 0 |
| 57 | 0 |
| 58 | 1653 |
| 59 | 1710 |
| 60 | 1770 |
| 61 | 1829 |
| 62 | 0 |
| 63 | 0 |
| 64 | 0 |
| 65 | 0 |
| 66 | 2145 |
| 67 | 2210 |
| 68 | 0 |
| 69 | 0 |
| 70 | 2415 |
[0,1,2,6,9,15,20,0,0,45,54,66,77,0,0,120,135,153, 170,0,0,231,252,0,0,0,0,378,405,435,464,0,0,0,0, 630,665,0,0,780,819,861,902,0,0,1035,1080,0,0,0,0, 1326,1377,0,0,0,0,1653,1710,1770,1829,0,0,0,0, 2145,2210,0,0,2415] |