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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 31 |
| 4 | 154 |
| 5 | 763 |
| 6 | 3808 |
| 7 | 19197 |
| 8 | 97772 |
| 9 | 502749 |
| 10 | 2607658 |
| 11 | 13630635 |
| 12 | 71743478 |
| 13 | 379949431 |
| 14 | 2023314980 |
| 15 | 10828048409 |
| 16 | 58206726936 |
| 17 | 314157742457 |
| 18 | 1701817879214 |
| 19 | 9249717805207 |
| 20 | 50427858276754 |
| 21 | 275695956722547 |
| 22 | 1511164724634440 |
| 23 | 8302888160922965 |
[1,6,31,154,763,3808,19197,97772,502749,2607658, 13630635,71743478,379949431,2023314980, 10828048409,58206726936,314157742457, 1701817879214,9249717805207,50427858276754, 275695956722547,1511164724634440,8302888160922965] |