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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 1 |
| 6 | 1 |
| 7 | 28 |
| 8 | 28 |
| 9 | 1 |
| 10 | 1 |
| 11 | 133 |
| 12 | 931 |
| 13 | 133 |
| 14 | 1 |
| 15 | 1 |
| 16 | 760 |
| 17 | 25270 |
| 18 | 25270 |
| 19 | 760 |
| 20 | 1 |
| 21 | 1 |
| 22 | 3880 |
| 23 | 737200 |
| 24 | 3501700 |
| 25 | 737200 |
| 26 | 3880 |
| 27 | 1 |
| 28 | 1 |
| 29 | 21049 |
| 30 | 20417530 |
| 31 | 554190100 |
| 32 | 554190100 |
| 33 | 20417530 |
| 34 | 21049 |
| 35 | 1 |
| 36 | 1 |
| 37 | 110236 |
| 38 | 580089391 |
| 39 | 80383815610 |
| 40 | 459336089200 |
[1,1,1,1,4,1,1,28,28,1,1,133,931,133,1,1,760, 25270,25270,760,1,1,3880,737200,3501700,737200, 3880,1,1,21049,20417530,554190100,554190100, 20417530,21049,1,1,110236,580089391,80383815610, 459336089200] |