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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 1 |
| 4 | 12 |
| 5 | 42 |
| 6 | 44 |
| 7 | 9 |
| 8 | 1 |
| 9 | 27 |
| 10 | 270 |
| 11 | 1278 |
| 12 | 3078 |
| 13 | 3888 |
| 14 | 2592 |
| 15 | 918 |
| 16 | 189 |
| 17 | 21 |
| 18 | 1 |
| 19 | 48 |
| 20 | 936 |
| 21 | 9744 |
| 22 | 60132 |
| 23 | 232560 |
| 24 | 585576 |
| 25 | 989424 |
| 26 | 1151910 |
| 27 | 949136 |
| 28 | 571608 |
| 29 | 261360 |
| 30 | 93540 |
| 31 | 26160 |
| 32 | 5400 |
| 33 | 720 |
| 34 | 45 |
| 35 | 1 |
| 36 | 75 |
| 37 | 2400 |
| 38 | 43400 |
| 39 | 496200 |
| 40 | 3812640 |
| 41 | 20493900 |
| 42 | 79452300 |
| 43 | 227904675 |
| 44 | 494715775 |
| 45 | 829703340 |
| 46 | 1096775400 |
| 47 | 1165877050 |
| 48 | 1017460800 |
| 49 | 744417900 |
| 50 | 465554460 |
| 51 | 252490875 |
| 52 | 119428125 |
| 53 | 49008500 |
| 54 | 17175000 |
| 55 | 5015100 |
| 56 | 1180200 |
| 57 | 213900 |
| 58 | 27900 |
| 59 | 2325 |
| 60 | 93 |
[1,1,3,1,12,42,44,9,1,27,270,1278,3078,3888,2592, 918,189,21,1,48,936,9744,60132,232560,585576, 989424,1151910,949136,571608,261360,93540,26160, 5400,720,45,1,75,2400,43400,496200,3812640, 20493900,79452300,227904675,494715775,829703340, 1096775400,1165877050,1017460800,744417900, 465554460,252490875,119428125,49008500,17175000, 5015100,1180200,213900,27900,2325,93] |