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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 22 |
| 2 | 148 |
| 3 | 1030 |
| 4 | 7204 |
| 5 | 50422 |
| 6 | 352948 |
| 7 | 2470630 |
| 8 | 17294404 |
| 9 | 121060822 |
| 10 | 847425748 |
| 11 | 5931980230 |
| 12 | 41523861604 |
| 13 | 290667031222 |
| 14 | 2034669218548 |
| 15 | 14242684529830 |
| 16 | 99698791708804 |
| 17 | 697891541961622 |
| 18 | 4885240793731348 |
| 19 | 34196685556119430 |
[4,22,148,1030,7204,50422,352948,2470630,17294404, 121060822,847425748,5931980230,41523861604, 290667031222,2034669218548,14242684529830, 99698791708804,697891541961622,4885240793731348, 34196685556119430] |