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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 17 |
| 3 | 69 |
| 4 | 281 |
| 5 | 1129 |
| 6 | 4521 |
| 7 | 18089 |
| 8 | 72361 |
| 9 | 289449 |
| 10 | 1157801 |
| 11 | 4631209 |
| 12 | 18524841 |
| 13 | 74099369 |
| 14 | 296397481 |
| 15 | 1185589929 |
[1,5,17,69,281,1129,4521,18089,72361,289449, 1157801,4631209,18524841,74099369,296397481, 1185589929] |