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| n | a(n) |
|---|---|
| 0 | 6 |
| 1 | 13 |
| 2 | 39 |
| 3 | 130 |
| 4 | 455 |
| 5 | 1638 |
| 6 | 6006 |
| 7 | 22308 |
| 8 | 83655 |
| 9 | 316030 |
| 10 | 1200914 |
| 11 | 4585308 |
| 12 | 17577014 |
| 13 | 67603887 |
| 14 | 260757536 |
| 15 | 1008258225 |
| 16 | 3906958055 |
| 17 | 15167837542 |
| 18 | 58983478554 |
| 19 | 229708325847 |
| 20 | 895760071050 |
| 21 | 3497141791455 |
| 22 | 13667427167576 |
| 23 | 53464307173927 |
| 24 | 209315686335366 |
| 25 | 820090746381088 |
| 26 | 3215215287887889 |
[6,13,39,130,455,1638,6006,22308,83655,316030, 1200914,4585308,17577014,67603887,260757536, 1008258225,3906958055,15167837542,58983478554, 229708325847,895760071050,3497141791455, 13667427167576,53464307173927,209315686335366, 820090746381088,3215215287887889] |