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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 22 |
| 4 | 105 |
| 5 | 518 |
| 6 | 2555 |
| 7 | 12565 |
| 8 | 61748 |
| 9 | 303470 |
| 10 | 1491567 |
| 11 | 7331205 |
| 12 | 36033501 |
| 13 | 177107406 |
| 14 | 870496256 |
| 15 | 4278555247 |
| 16 | 21029425081 |
| 17 | 103361226864 |
| 18 | 508028305120 |
| 19 | 2496997824041 |
| 20 | 12272934541014 |
| 21 | 60322408298439 |
| 22 | 296489232532277 |
| 23 | 1457267166329605 |
| 24 | 7162579146364783 |
[1,5,22,105,518,2555,12565,61748,303470,1491567, 7331205,36033501,177107406,870496256,4278555247, 21029425081,103361226864,508028305120, 2496997824041,12272934541014,60322408298439, 296489232532277,1457267166329605,7162579146364783] |