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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 16 |
| 3 | 56 |
| 4 | 178 |
| 5 | 669 |
| 6 | 2615 |
| 7 | 9573 |
| 8 | 35581 |
| 9 | 133149 |
| 10 | 495719 |
| 11 | 1845526 |
| 12 | 6880247 |
| 13 | 25634622 |
| 14 | 95503501 |
| 15 | 355868278 |
| 16 | 1325975629 |
| 17 | 4940513437 |
| 18 | 18408548266 |
| 19 | 68590644744 |
| 20 | 255569164599 |
| 21 | 952255335447 |
| 22 | 3548119872982 |
| 23 | 13220347086909 |
| 24 | 49259228193957 |
[1,16,56,178,669,2615,9573,35581,133149,495719, 1845526,6880247,25634622,95503501,355868278, 1325975629,4940513437,18408548266,68590644744, 255569164599,952255335447,3548119872982, 13220347086909,49259228193957] |