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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 1 |
| 6 | 10 |
| 7 | 1 |
| 8 | 2 |
| 9 | 280 |
| 10 | 2 |
| 11 | 10 |
| 12 | 235200 |
| 13 | 4 |
| 14 | 20 |
| 15 | 280 |
| 16 | 173859840000 |
| 17 | 40 |
| 18 | 2800 |
| 19 | 235200 |
| 20 | 98238542885683200000000 |
| 21 | 100 |
| 22 | 11200 |
| 23 | 65856000 |
| 24 | 173859840000 |
| 25 | 32169371027674057560745102540800000000000000000 |
| 26 | 28000 |
| 27 | 1317120000 |
[1,1,1,2,1,10,1,2,280,2,10,235200,4,20,280, 173859840000,40,2800,235200, 98238542885683200000000,100,11200,65856000, 173859840000, 32169371027674057560745102540800000000000000000, 28000,1317120000] |