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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 42 |
| 5 | 146 |
| 6 | 513 |
| 7 | 1814 |
| 8 | 6457 |
| 9 | 23852 |
| 10 | 88822 |
| 11 | 331756 |
| 12 | 1241569 |
| 13 | 4704536 |
| 14 | 17919729 |
| 15 | 68426280 |
| 16 | 261659138 |
| 17 | 1005583928 |
| 18 | 3876858984 |
| 19 | 14975423376 |
| 20 | 57918225459 |
| 21 | 224542599510 |
| 22 | 872234912198 |
| 23 | 3393031324338 |
| 24 | 13212674724177 |
[1,2,5,14,42,146,513,1814,6457,23852,88822,331756, 1241569,4704536,17919729,68426280,261659138, 1005583928,3876858984,14975423376,57918225459, 224542599510,872234912198,3393031324338, 13212674724177] |