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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 61 |
| 5 | 301 |
| 6 | 1552 |
| 7 | 8277 |
| 8 | 45284 |
| 9 | 252753 |
| 10 | 1433633 |
| 11 | 8239993 |
| 12 | 47887467 |
| 13 | 280927846 |
| 14 | 1661387046 |
| 15 | 9894376821 |
| 16 | 59288650788 |
| 17 | 357198545904 |
| 18 | 2162437157263 |
| 19 | 13147835385477 |
| 20 | 80251977589719 |
| 21 | 491573099486143 |
| 22 | 3020738578507674 |
| 23 | 18617035563669489 |
| 24 | 115046892012376542 |
| 25 | 712710925868858139 |
| 26 | 4425312432316379040 |
| 27 | 27535525144298975942 |
| 28 | 171670784266383750322 |
| 29 | 1072246008621559982926 |
| 30 | 6708644077265798380125 |
[1,3,13,61,301,1552,8277,45284,252753,1433633, 8239993,47887467,280927846,1661387046,9894376821, 59288650788,357198545904,2162437157263, 13147835385477,80251977589719,491573099486143, 3020738578507674,18617035563669489, 115046892012376542,712710925868858139, 4425312432316379040,27535525144298975942, 171670784266383750322,1072246008621559982926, 6708644077265798380125] |