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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 25 |
| 6 | 27 |
| 7 | 33 |
| 8 | 42 |
| 9 | 221 |
| 10 | 274 |
| 11 | 581 |
| 12 | 1957 |
| 13 | 3125 |
| 14 | 11406 |
| 15 | 47058 |
| 16 | 823543 |
| 17 | 1535573 |
| 18 | 5056941 |
| 19 | 19246541 |
| 20 | 19571621 |
| 21 | 36861842 |
| 22 | 50330577 |
| 23 | 2590282517 |
| 24 | 45546909393 |
[1,2,4,6,25,27,33,42,221,274,581,1957,3125,11406, 47058,823543,1535573,5056941,19246541,19571621, 36861842,50330577,2590282517,45546909393] |