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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 13 |
| 3 | 29 |
| 4 | 112 |
| 5 | 515 |
| 6 | 2713 |
| 7 | 12669 |
| 8 | 59569 |
| 9 | 295903 |
| 10 | 1439748 |
| 11 | 6946321 |
| 12 | 33748534 |
| 13 | 164163421 |
| 14 | 796809315 |
| 15 | 3867558936 |
| 16 | 18785049041 |
| 17 | 91228838297 |
| 18 | 442968357392 |
| 19 | 2151023744989 |
| 20 | 10445663389464 |
| 21 | 50723981600714 |
| 22 | 246313304788613 |
[2,13,29,112,515,2713,12669,59569,295903,1439748, 6946321,33748534,164163421,796809315,3867558936, 18785049041,91228838297,442968357392, 2151023744989,10445663389464,50723981600714, 246313304788613] |