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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 33 |
| 3 | 109 |
| 4 | 349 |
| 5 | 2430 |
| 6 | 11345 |
| 7 | 50127 |
| 8 | 267505 |
| 9 | 1348969 |
| 10 | 6648889 |
| 11 | 34251499 |
| 12 | 175903584 |
| 13 | 898599371 |
| 14 | 4639188241 |
| 15 | 23998716363 |
| 16 | 124089900743 |
| 17 | 643458024265 |
| 18 | 3340939446919 |
| 19 | 17352516058844 |
| 20 | 90210216214327 |
| 21 | 469258501795259 |
[1,33,109,349,2430,11345,50127,267505,1348969, 6648889,34251499,175903584,898599371,4639188241, 23998716363,124089900743,643458024265, 3340939446919,17352516058844,90210216214327, 469258501795259] |