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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 7 |
| 4 | 40 |
| 5 | 47 |
| 6 | 275 |
| 7 | 597 |
| 8 | 872 |
| 9 | 3213 |
| 10 | 36215 |
| 11 | 111858 |
| 12 | 148073 |
| 13 | 704150 |
| 14 | 6485423 |
| 15 | 7189573 |
| 16 | 49622861 |
| 17 | 56812434 |
| 18 | 220060163 |
| 19 | 716992923 |
| 20 | 937053086 |
| 21 | 4465205267 |
| 22 | 9867463620 |
| 23 | 14332668887 |
| 24 | 24200132507 |
| 25 | 86933066408 |
| 26 | 111133198915 |
| 27 | 420332663153 |
| 28 | 1792463851527 |
[2,5,7,40,47,275,597,872,3213,36215,111858,148073, 704150,6485423,7189573,49622861,56812434, 220060163,716992923,937053086,4465205267, 9867463620,14332668887,24200132507,86933066408, 111133198915,420332663153,1792463851527] |