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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 109 |
| 3 | 685 |
| 4 | 4483 |
| 5 | 29469 |
| 6 | 193531 |
| 7 | 1270657 |
| 8 | 8343063 |
| 9 | 54780825 |
| 10 | 359691769 |
| 11 | 2361740413 |
| 12 | 15507217849 |
| 13 | 101820594071 |
| 14 | 668555339287 |
| 15 | 4389743011111 |
| 16 | 28823109441929 |
| 17 | 189252909756115 |
| 18 | 1242637055605621 |
| 19 | 8159170994793111 |
[15,109,685,4483,29469,193531,1270657,8343063, 54780825,359691769,2361740413,15507217849, 101820594071,668555339287,4389743011111, 28823109441929,189252909756115,1242637055605621, 8159170994793111] |