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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 14 |
| 3 | 71 |
| 4 | 370 |
| 5 | 1950 |
| 6 | 10332 |
| 7 | 54895 |
| 8 | 292106 |
| 9 | 1555706 |
| 10 | 8289732 |
| 11 | 44186710 |
| 12 | 235575028 |
| 13 | 1256093084 |
| 14 | 6698073528 |
| 15 | 35719158591 |
| 16 | 190488112122 |
| 17 | 1015885525794 |
| 18 | 5417869631028 |
| 19 | 28894620083346 |
| 20 | 154102115782812 |
[1,3,14,71,370,1950,10332,54895,292106,1555706, 8289732,44186710,235575028,1256093084,6698073528, 35719158591,190488112122,1015885525794, 5417869631028,28894620083346,154102115782812] |