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| n | a(n) |
|---|---|
| 1 | 1215 |
| 2 | 1511 |
| 3 | 5401 |
| 4 | 22922 |
| 5 | 96649 |
| 6 | 409196 |
| 7 | 1741500 |
| 8 | 7424379 |
| 9 | 31630192 |
| 10 | 134638409 |
| 11 | 573239769 |
| 12 | 2441382476 |
| 13 | 10396957545 |
| 14 | 44272817726 |
| 15 | 188528190560 |
| 16 | 802834481337 |
| 17 | 3418801560572 |
| 18 | 14558580766123 |
| 19 | 61996115520891 |
| 20 | 264004067912028 |
[1215,1511,5401,22922,96649,409196,1741500, 7424379,31630192,134638409,573239769,2441382476, 10396957545,44272817726,188528190560,802834481337, 3418801560572,14558580766123,61996115520891, 264004067912028] |