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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 25 |
| 3 | 118 |
| 4 | 468 |
| 5 | 1501 |
| 6 | 4167 |
| 7 | 10423 |
| 8 | 24115 |
| 9 | 52449 |
| 10 | 108395 |
| 11 | 214496 |
| 12 | 408732 |
| 13 | 753333 |
| 14 | 1347741 |
| 15 | 2347301 |
| 16 | 3989727 |
| 17 | 6631953 |
| 18 | 10800653 |
| 19 | 17260510 |
| 20 | 27105244 |
| 21 | 41877485 |
| 22 | 63724811 |
| 23 | 95600675 |
| 24 | 141520531 |
| 25 | 206885249 |
| 26 | 298885895 |
| 27 | 427006156 |
| 28 | 603641124 |
[5,25,118,468,1501,4167,10423,24115,52449,108395, 214496,408732,753333,1347741,2347301,3989727, 6631953,10800653,17260510,27105244,41877485, 63724811,95600675,141520531,206885249,298885895, 427006156,603641124] |