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| n | a(n) |
|---|---|
| 1 | 48 |
| 2 | 222 |
| 3 | 1049 |
| 4 | 4348 |
| 5 | 17658 |
| 6 | 67012 |
| 7 | 247639 |
| 8 | 880814 |
| 9 | 3061429 |
| 10 | 10385988 |
| 11 | 34604232 |
| 12 | 113376954 |
| 13 | 366386257 |
| 14 | 1169544994 |
| 15 | 3694214596 |
| 16 | 11560700652 |
| 17 | 35884753502 |
| 18 | 110586677426 |
| 19 | 338628074707 |
| 20 | 1031035016352 |
| 21 | 3123343642588 |
| 22 | 9418695537368 |
[48,222,1049,4348,17658,67012,247639,880814, 3061429,10385988,34604232,113376954,366386257, 1169544994,3694214596,11560700652,35884753502, 110586677426,338628074707,1031035016352, 3123343642588,9418695537368] |