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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 25 |
| 3 | 109 |
| 4 | 477 |
| 5 | 1981 |
| 6 | 8061 |
| 7 | 32509 |
| 8 | 130557 |
| 9 | 523261 |
| 10 | 2095101 |
| 11 | 8384509 |
| 12 | 33546237 |
| 13 | 134201341 |
| 14 | 536838141 |
| 15 | 2147418109 |
[1,5,25,109,477,1981,8061,32509,130557,523261, 2095101,8384509,33546237,134201341,536838141, 2147418109] |