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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 53 |
| 5 | 286 |
| 6 | 2227 |
| 7 | 16682 |
| 8 | 164089 |
| 9 | 1619506 |
| 10 | 19139231 |
| 11 | 228289282 |
| 12 | 3233324437 |
| 13 | 45177961154 |
| 14 | 727739459371 |
| 15 | 11876754782146 |
| 16 | 215081192780657 |
| 17 | 3943187021584642 |
| 18 | 80187760712122039 |
| 19 | 1635670770628012706 |
[1,3,10,53,286,2227,16682,164089,1619506,19139231, 228289282,3233324437,45177961154,727739459371, 11876754782146,215081192780657,3943187021584642, 80187760712122039,1635670770628012706] |