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| n | a(n) |
|---|---|
| 11 | 1 |
| 12 | 12 |
| 13 | 133 |
| 14 | 1125 |
| 15 | 9238 |
| 16 | 68619 |
| 17 | 499415 |
| 18 | 3490873 |
| 19 | 24131903 |
| 20 | 163571510 |
| 21 | 1103866052 |
| 22 | 7385297559 |
| 23 | 49389978105 |
| 24 | 329450566234 |
| 25 | 2201955344742 |
| 26 | 14731655532265 |
| 27 | 98920296206493 |
| 28 | 666337183741714 |
| 29 | 4510099063773320 |
| 30 | 30665172472203015 |
| 31 | 209659934046564822 |
| 32 | 1441217280964444721 |
[1,12,133,1125,9238,68619,499415,3490873,24131903, 163571510,1103866052,7385297559,49389978105, 329450566234,2201955344742,14731655532265, 98920296206493,666337183741714,4510099063773320, 30665172472203015,209659934046564822, 1441217280964444721] |