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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 17 |
| 5 | 45 |
| 6 | 176 |
| 7 | 644 |
| 8 | 2983 |
| 9 | 13675 |
| 10 | 67487 |
| 11 | 340192 |
| 12 | 1775300 |
| 13 | 9438436 |
| 14 | 51112686 |
| 15 | 281006680 |
| 16 | 1565898705 |
| 17 | 8826775421 |
| 18 | 50268025897 |
| 19 | 288898607594 |
| 20 | 1674035743383 |
| 21 | 9772219545537 |
| 22 | 57429659103938 |
| 23 | 339574982244340 |
| 24 | 2019144043582652 |
| 25 | 12067931396139136 |
[1,3,4,17,45,176,644,2983,13675,67487,340192, 1775300,9438436,51112686,281006680,1565898705, 8826775421,50268025897,288898607594,1674035743383, 9772219545537,57429659103938,339574982244340, 2019144043582652,12067931396139136] |