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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 1 |
| 4 | 3 |
| 5 | 6 |
| 6 | 1 |
| 7 | 4 |
| 8 | 18 |
| 9 | 70 |
| 10 | 1 |
| 11 | 5 |
| 12 | 40 |
| 13 | 1407 |
| 14 | 93024 |
| 15 | 1 |
| 16 | 6 |
| 17 | 75 |
| 18 | 12480 |
| 19 | 294157089 |
| 20 | 47823602694208 |
| 21 | 1 |
| 22 | 7 |
| 23 | 126 |
| 24 | 69050 |
| 25 | 91983927296 |
| 26 | 67514530382043163023924 |
| 27 | 443077371786837979607993095063601152 |
| 28 | 1 |
[1,2,1,3,6,1,4,18,70,1,5,40,1407,93024,1,6,75, 12480,294157089,47823602694208,1,7,126,69050, 91983927296,67514530382043163023924, 443077371786837979607993095063601152,1] |