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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 23 |
| 4 | 86 |
| 5 | 313 |
| 6 | 1145 |
| 7 | 4184 |
| 8 | 15293 |
| 9 | 55895 |
| 10 | 204294 |
| 11 | 746685 |
| 12 | 2729101 |
| 13 | 9974744 |
| 14 | 36457249 |
| 15 | 133249635 |
| 16 | 487021534 |
| 17 | 1780042209 |
| 18 | 6505975697 |
| 19 | 23779053976 |
| 20 | 86911392597 |
| 21 | 317657303391 |
| 22 | 1161023421462 |
| 23 | 4243489354069 |
| 24 | 15509766267621 |
[1,7,23,86,313,1145,4184,15293,55895,204294, 746685,2729101,9974744,36457249,133249635, 487021534,1780042209,6505975697,23779053976, 86911392597,317657303391,1161023421462, 4243489354069,15509766267621] |