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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 65 |
| 5 | 261 |
| 6 | 1085 |
| 7 | 4571 |
| 8 | 19587 |
| 9 | 84885 |
| 10 | 371691 |
| 11 | 1640097 |
| 12 | 7286299 |
| 13 | 32554855 |
| 14 | 146180405 |
| 15 | 659196933 |
| 16 | 2984034309 |
| 17 | 13553661103 |
| 18 | 61747484695 |
| 19 | 282070090245 |
| 20 | 1291711612597 |
| 21 | 5928513573073 |
| 22 | 27265526668561 |
| 23 | 125631143092757 |
| 24 | 579873415046605 |
| 25 | 2680800605312565 |
| 26 | 12411974059778039 |
| 27 | 57546369699984959 |
[1,1,5,17,65,261,1085,4571,19587,84885,371691, 1640097,7286299,32554855,146180405,659196933, 2984034309,13553661103,61747484695,282070090245, 1291711612597,5928513573073,27265526668561, 125631143092757,579873415046605,2680800605312565, 12411974059778039,57546369699984959] |