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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 6 |
| 4 | 34 |
| 5 | 286 |
| 6 | 3194 |
| 7 | 44486 |
| 8 | 742482 |
| 9 | 14444046 |
| 10 | 320918346 |
| 11 | 8017473462 |
| 12 | 222470403426 |
| 13 | 6788415920190 |
| 14 | 225916032873498 |
| 15 | 8143297424571942 |
| 16 | 316056720170045682 |
| 17 | 13141075984919431662 |
| 18 | 582736651766946778986 |
[2,2,6,34,286,3194,44486,742482,14444046, 320918346,8017473462,222470403426,6788415920190, 225916032873498,8143297424571942, 316056720170045682,13141075984919431662, 582736651766946778986] |