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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 17 |
| 3 | 49 |
| 4 | 261 |
| 5 | 1081 |
| 6 | 3993 |
| 7 | 15521 |
| 8 | 61921 |
| 9 | 248613 |
| 10 | 997825 |
| 11 | 3981665 |
| 12 | 15954309 |
| 13 | 63723117 |
| 14 | 255045061 |
| 15 | 1019793809 |
[1,5,17,49,261,1081,3993,15521,61921,248613, 997825,3981665,15954309,63723117,255045061, 1019793809] |