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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 17 |
| 4 | 71 |
| 5 | 169 |
| 6 | 703 |
| 7 | 1673 |
| 8 | 6959 |
| 9 | 16561 |
| 10 | 68887 |
| 11 | 163937 |
| 12 | 681911 |
| 13 | 1622809 |
| 14 | 6750223 |
| 15 | 16064153 |
| 16 | 66820319 |
| 17 | 159018721 |
| 18 | 661452967 |
| 19 | 1574123057 |
| 20 | 6547709351 |
| 21 | 15582211849 |
| 22 | 64815640543 |
| 23 | 154247995433 |
| 24 | 641608696079 |
| 25 | 1526897742481 |
| 26 | 6351271320247 |
| 27 | 15114729429377 |
| 28 | 62871104506391 |
[1,7,17,71,169,703,1673,6959,16561,68887,163937, 681911,1622809,6750223,16064153,66820319, 159018721,661452967,1574123057,6547709351, 15582211849,64815640543,154247995433,641608696079, 1526897742481,6351271320247,15114729429377, 62871104506391] |