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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 6 |
| 5 | 12 |
| 6 | 31 |
| 7 | 78 |
| 8 | 234 |
| 9 | 722 |
| 10 | 2376 |
| 11 | 8046 |
| 12 | 28263 |
| 13 | 101226 |
| 14 | 370389 |
| 15 | 1375728 |
| 16 | 5182107 |
| 17 | 19743204 |
| 18 | 75994993 |
| 19 | 295110996 |
| 20 | 1155128397 |
| 21 | 4553360558 |
| 22 | 18063221619 |
| 23 | 72069527418 |
| 24 | 289053637621 |
| 25 | 1164871141254 |
| 26 | 4714973350560 |
| 27 | 19161577759814 |
| 28 | 78162897838290 |
| 29 | 319940064689142 |
[2,3,4,6,12,31,78,234,722,2376,8046,28263,101226, 370389,1375728,5182107,19743204,75994993, 295110996,1155128397,4553360558,18063221619, 72069527418,289053637621,1164871141254, 4714973350560,19161577759814,78162897838290, 319940064689142] |