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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 7 |
| 6 | 2 |
| 7 | 10 |
| 8 | 51 |
| 9 | 51 |
| 10 | 10 |
| 11 | 24 |
| 12 | 391 |
| 13 | 737 |
| 14 | 391 |
| 15 | 24 |
| 16 | 72 |
| 17 | 2894 |
| 18 | 19446 |
| 19 | 19446 |
| 20 | 2894 |
| 21 | 72 |
| 22 | 168 |
| 23 | 22491 |
| 24 | 292257 |
| 25 | 1020085 |
| 26 | 292257 |
| 27 | 22491 |
| 28 | 168 |
| 29 | 664 |
| 30 | 173099 |
| 31 | 7998180 |
| 32 | 54792022 |
| 33 | 54792022 |
| 34 | 7998180 |
| 35 | 173099 |
| 36 | 664 |
| 37 | 1632 |
| 38 | 1351439 |
| 39 | 124148448 |
| 40 | 2987881000 |
[1,1,1,2,7,2,10,51,51,10,24,391,737,391,24,72, 2894,19446,19446,2894,72,168,22491,292257,1020085, 292257,22491,168,664,173099,7998180,54792022, 54792022,7998180,173099,664,1632,1351439, 124148448,2987881000] |