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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 55 |
| 3 | 384 |
| 4 | 3477 |
| 5 | 30071 |
| 6 | 259856 |
| 7 | 2253537 |
| 8 | 19514155 |
| 9 | 169056920 |
| 10 | 1464412705 |
| 11 | 12685404677 |
| 12 | 109886670038 |
| 13 | 951885707773 |
| 14 | 8245652221757 |
| 15 | 71427443730770 |
| 16 | 618735770258261 |
| 17 | 5359759927360759 |
| 18 | 46428585278694262 |
| 19 | 402184717612536457 |
[3,55,384,3477,30071,259856,2253537,19514155, 169056920,1464412705,12685404677,109886670038, 951885707773,8245652221757,71427443730770, 618735770258261,5359759927360759, 46428585278694262,402184717612536457] |