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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 34 |
| 5 | 156 |
| 6 | 635 |
| 7 | 2966 |
| 8 | 14327 |
| 9 | 66047 |
| 10 | 314700 |
| 11 | 1560159 |
| 12 | 7710390 |
| 13 | 38251395 |
| 14 | 192549444 |
| 15 | 974601369 |
| 16 | 4952273462 |
| 17 | 25349634715 |
| 18 | 130414412847 |
| 19 | 673028519274 |
| 20 | 3487306501970 |
| 21 | 18139905710007 |
| 22 | 94640387701755 |
| 23 | 495160150021161 |
| 24 | 2597800048395361 |
| 25 | 13661957722514619 |
[1,3,7,34,156,635,2966,14327,66047,314700,1560159, 7710390,38251395,192549444,974601369,4952273462, 25349634715,130414412847,673028519274, 3487306501970,18139905710007,94640387701755, 495160150021161,2597800048395361, 13661957722514619] |