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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 27 |
| 4 | 111 |
| 5 | 470 |
| 6 | 2029 |
| 7 | 8960 |
| 8 | 40297 |
| 9 | 182778 |
| 10 | 836559 |
| 11 | 3855341 |
| 12 | 17894213 |
| 13 | 83532220 |
| 14 | 391593043 |
| 15 | 1843022301 |
| 16 | 8705626983 |
| 17 | 41256214000 |
| 18 | 196078437757 |
| 19 | 934180171615 |
| 20 | 4460906744163 |
| 21 | 21346947146028 |
| 22 | 102348842762445 |
| 23 | 491573645206032 |
| 24 | 2364729672893783 |
| 25 | 11392440575953112 |
| 26 | 54960687274556733 |
| 27 | 265485535655291855 |
[1,2,7,27,111,470,2029,8960,40297,182778,836559, 3855341,17894213,83532220,391593043,1843022301, 8705626983,41256214000,196078437757,934180171615, 4460906744163,21346947146028,102348842762445, 491573645206032,2364729672893783, 11392440575953112,54960687274556733, 265485535655291855] |